NANOMATERIALS & ARCHITECTURE A SCIENTIFIC …api.ning.com/files/zJEntOuSjcPOSPKM1vDsdrMca7... · A...

NANOMATERIALS & ARCHITECTURE "SUSTAINABLE NANOARCHITECTURE"

A SCIENTIFIC REPORT

Presented to the Graduate School Faculty of Engineering, Alexandria University

In Partial Fulfillment of the Requirements for the Degree

Of

Master of Engineering

In

Architecture Engineering

By

Mohamed Hazem Mohamed Fahmy

May 2010

NANOMATERIALS & ARCHITECTURE "SUSTAINABLE NANOARCHITECTURE"

Presented by Mohamed Hazem Mohamed Fahmy

For The Degree of

Master of Engineering

In

Architecture Ebgibeering By

Mohamed Hazem Mohamed Fahmy

Examiners' Committee: Approved

Prof. Dr. Mohamed Abdelall Ibrahim ……………… Professor of architecture, department of architecture, Faculty of Engineering, University of Alexandria

Prof. Dr. Mohamed Tarek AlSayad ……………… Professor of architecture, department of architecture, Faculty of Engineering, University of Alexandria

Prof. Dr. Nadia S. El-Baghdady ……………… Professor of architecture, department of architecture, Faculty of Engineering, University of Alexandria

Vice Dean for Graduate Studies and Research

Prof. Dr.: Ibtehal Y. El-Bastawissi

Advisors' Committee:

Prof. Dr. Mohamed Abdelall Ibrahim ……………… Professor of architecture, department of architecture, Faculty of Engineering, University of Alexandria

III

ACKNOWLEDGMENT

I would like to thank Professor Dr. Mohamed AbdelAll Ibrahim, department

of architecture, Faculty of Engineering, University of Alexandria, for his generous,

useful comments, help, precious advice, time and effort throughout all the stages of

conducting this thesis.

I also would like to thank my family for helping me, saving time and their

efforts thought all of the stages of thesis.

Mohamed H. Fahmy

IV

TABLE OF CONTENTS

Examiners Committee………………………………………………………………………... Advisors Committee………………………………………………………………………….. Acknowledgement……………………………………………………………………………. Table of Contents…………………………………………………………………………….. List of Figures………………………………………………………………………………… List of Abbreviations…………………………………………………………………………. Research Structure…………………………………………………………………………… Introduction…………………………………………………………………………………... Research Objectives…………………………………………………………………………..

I II III IV VI X XI XII XIII

1. Chapter One - Nanotechnology:

1.1. Introduction………………………………………………………………………….. 1.2. What's Nano? ………………………………………………………………………..

1.2.1. A virtual discovery journey into the worlds of micro and Nano cosmos……… 1.3. Nanotechnology………………………………………………………………………

1.3.1. Definition……………………………………………………………………… 1.3.2. Origins…………………………………………………………………………. 1.3.3. Fundamental Concepts…………………………………………………………

1.4. Nanotechnology and Architecture (NanoArchitecture)…………………………... 1.5. The Future of Architecture with Nanotechnology…………………………………

1.5.1. Making the Technology More Humane……………………………………….. 1.5.2. Designing Your Own Materials……………………………………………….. 1.5.3. Buildings That Will "Grow"? …………………………………………………. 1.5.4. Responsive Architecture………………………………………………………. 1.5.5. Bringing Architecture Closer to Nature………………………………………..

1.6. Conclusion…………………………………………………………………………….

010303040404050608080809090912

2. Chapter Two - Nanomaterials Products:

2.1. Introduction………………………………………………………………………….. 2.2. Nanomaterials………………………………………………………………………...

2.2.1. Background……………………………………………………………………. 2.2.2. Scale…………………………………………………………………………… 2.2.3. Structure Dimensions…………………………………………………………..

2.2.3.1. Nanoscale in One Dimension…………………………………………. 2.2.3.2. Nanoscale in Two Dimension…………………………………………. 2.2.3.3. Nanoscale in Three Dimension………………………………………...

2.2.4. Classification…………………………………………………………………... 2.2.4.1. Fullerenes……………………………………………………………… 2.2.4.2. Inorganic Nanoparticles………………………………………………..

2.3. Nanomaterials Products and Benefits……………………………………………… 2.3.1. Coatings………………………………………………………………………..

2.3.1.1. Self-Cleaning: Lotus-Effect…………………………………………… 2.3.1.2. Self-Cleaning: Photocatalysis…………………………………………. 2.3.1.3. Easy-To-Clean (ETC)…………………………………………………. 2.3.1.4. Antibacterial……………………………………………………………

2.3.2. Insulation………………………………………………………………………

131414151616171819191920212224283032

V

2.3.2.1. Thermal Insulation: Vacuum Insulation Panels (VIPs)……………….. 2.3.2.2. Thermal Insulation: Aerogel…………………………………………... 2.3.2.3. Temperature Regulation: Phase Change Material (PCMs)…………….

2.3.3. Air-Purifying…………………………………………………………………... 2.3.3.1. Indoors………………………………………………………………… 2.3.3.2. Outdoors………………………………………………………………..

2.3.4. Solar Protection………………………………………………………………... 2.3.5. Fire-Proof……………………………………………………………………… 2.3.6. Scratchproof and abrasion-resistant……………………………………………

2.4. Nanomaterials Costs………………………………………………………………… 2.4.1. Types…………………………………………………………………………...

2.5. Nanomaterials in Architecture Design……………………………………………... 2.5.1. Design Focus…………………………………………………………………..

2.6. The Holistic Application of Nanosurfaces in Interiors……………………………. 2.7. Conclusion…………………………………………………………………………….

333537393940424345464648495152

3. Chapter Three – Future Applications of Nanomaterials in Architecture for

Sustainable Development:

3.1. Introduction………………………………………………………………………….. 3.2. Green Nanotechnology……………………………………………………………… 3.3. Nanomaterials in Sustainability and the Environment……………………………

3.3.1. Nanotechnology with Concrete and Steel……………………………………... 3.3.1.1. Carbon Nanotubes……………………………………………………..

3.4. Nanomaterials in Sustainability and the Energy………………………………….. 3.4.1. Energy production……………………………………………………………... 3.4.2. Thin-film Solar………………………………………………………………… 3.4.3. Organic light-emitting diode (OLED)…………………………………………. 3.4.4. Nanosensors……………………………………………………………………

3.5. Conclusion…………………………………………………………………………….

5354555658626364677074

General Conclusion and Recommendations………………………………………………... List of References…………………………………………………………………………….. …………………………………………………………………………ملخص الرساله باللغة العربية

757678

VI

LIST OF FIGURES

- Figure 1.1: Examples from biological and mechanical realms……………………… - Figure 1.2: NanoHouse Show the good design and benefits of using Nanomaterials… - Figure 1.3: Nano-journeys - adventures beyond the decimal………………………….. - Figure 1.4: Buckminster fullerene C60, also known as the buckyball…………………. - Figure 1.5: Sarfus image of a DNA biochip elaborated by bottom-up approach……… - Figure 1.6: This device transfers energy from Nano thin layers of quantum wells to

nanocrystals above them, causing the nanocrystals to emit visible light…………………… - Figure 1.7: The entire facade of the Nano tower is faceted, inspired by a Nano scale

carbon tube………………………………………………………………………………… - Figure 1.8: Variable mood lighting over a whole wall……………………………… - Figure 1.9: Relationship of nanotechnology to construction………………………….. - Figure 1.10: Nano Vent-Skin exterior………………………………………………… - Figure 1.11: Nano-structure components……………………………………………… - Figure 1.12: Community center……………………………………………………….. - Figure 1.13: The molecule design of community center……………………………… - Figure 1.14: Diagrams of the days of construction of the molecular-engineered house... - Figure 1.15: The Multistory growth building…………………………………………… - Figure 1.16: The sun Chapel, morphable structure responding to light energy following

the passage of the day……………………………………………………………………… - Figure 1.17: The natural walls of the Molecular engineered future house………………. - Figure 1.18: A Plan and longitudinal section of the Growing molecular-engineered

house……………………………………………………………………………………… - Figure 1.19: Exterior view of the Molecular engineered future house………………… - Figure 1.20: Diagrams of the days of construction of the molecular-engineered house…

- Figure 2.1: Nanomaterials categorized based on their dimensions……………………. - Figure 2.2: Length scales ranging from the subatomic through molecular, human, and

terrestrial to astronomic. The Nano range is shown on the lower right…………………….. - Figure 2.3: The fraction of atoms that lie in the surface or internal interfaces of a

nanoscale or nanostructured material, expressed as a percentage (%)…………………… - Figure 2.4: Thin-solar Film……………………………………………………………. - Figure 2.5: Image of Carbon Nanotubes structure…………………………………….. - Figure 2.6: Silica Nanowire…………………………………………………………… - Figure 2.7: Microscopic image of Nanoparticle………………………………………. - Figure 2.8: C60 spherical molecules………………………………………………… - Figure 2.9: C60 with isosurface of ground state electron density as calculated with

DFT………………………………………………………………………………………… - Figure 2.10: TEM (a, b, and c) images of prepared mesoporous silica nanoparticles

with mean outer diameter………………………………………………………………… - Figure 2.11: The Lotus plant with its natural self-cleaning qualities lends its name to

the "Lotus-Effect"………………………………………………………………………… - Figure 2.12: A microscopic view of a water droplet resting on a super hydrophic and

visibly knobbly surface……………………………………………………………………... - Figure 2.13: The micro-structure of the surface of a Façade coated with a

nanotechnology-engineered Lotus-Effect color coating emulates that of its natural namesake……………………………………………………………………………………

- Figure 2.14: Water channels formed by water droplets running off natural surfaces and a building Façade……………………………………………………………………………

- Figure 2.15: Ara Pacis Museum exterior, showing self cleaning coating……………… - Figure 2.16: The diagrams show clearly the difference between conventional surfaces

and the Lotus-Effect………………………………………………………………………

01 02 03 04 05

05

06 06 07 07 07 08 08 09 09

09 10

10 11 11

14

15

16 16 17 17 18 18

19

19

22

22

22

22 23

23

VII

- Figure 2.17: Ara Pacis Museum exterior………………………………………………… - Figure 2.18: Oleo phobic surfaces are resistant against oils and fats………………… - Figure 2.19: Before and after: On conventional tiles, water forms droplets that dry

leaving behind dirt deposits. On the hydrophilic surfaces of photocatalytic tiles, water forms a film that runs off taking any loose dirt deposits with it……………………………

- Figure 2.20: The diagrams show the bask process: Organic dirt and grime is broicen down and "decomposed"…………………………………………………………………….

- Figure 2.21: TiO2 and PVC coated white membranes in weathering tests. The difference is readily apparent: after five months the former is still white, the latter grey and unsightly………………………………………………………………………………

- Figure 2.22: Muhammad Ali Center MAC exterior…………………………………… - Figure 2.23: Ceramic tiles with self-cleaning Photocatalytic used in Muhammad Ali

Center MAC exterior façade………………………………………………………………... - Figure 2.24: Narita International Airport exterior………………………………………. - Figure 2.25: Narita International Airport exterior……………………………………… - Figure 2.26: "Roll-out marble"- Impact-resistant, fire-retardant, vapor permeable and

yet water-repellent and easy-to-clean……………………………………………………… - Figure 2.27: A comparison of ceramic surfaces – left without ETC coating, right with

ETC coating………………………………………………………………………………… - Figure 2.28: Ultra-clean white surfaces of poolside armchairs, achieved using water-

repellent surface coatings…………………………………………………………………… - Figure 2.29: The angle of contact determines the hydrophobic degree of a surface. The

contact angle describes the degree of wetting, and is a function of the relative surface tensions of the solid, water and air…………………………………………………………

- Figure 2.30: The enameled facade panels of Kaldewei Kompetenz-Center (KKC)……. - Figure 2.31: Kaldewei Kompetenz-Center (KKC) interior…………………………… - Figure 2.32: Kaldewei Kompetenz-Center (KKC) exterior…………………………… - Figure 2.33: Sanitary, care and medical facilities are areas particularly susceptible to

germ transmission. This can be counteracted through the use of antibacterial surface coatings that react against many of the more important pathogens…………………………

- Figure 2.34: Curtains with antibacterial properties……………………………………... - Figure 2.35: The mould on the facades of Housing estate……………………………… - Figure 2.36: The Antimicrobial paint was used on the façades of housing estate……… - Figure 2.37: Fiberglass insulation (OwensCorning)…………………………………… - Figure 2.38: Vacuum insulation panels with a protective encasement………………….. - Figure 2.39: VIP insulation must be made to measure and fitted precisely on site…… - Figure 2.40: Seitzstrasse mixed-use building…………………………………………… - Figure 2.41: Thermography of the building…………………………………………….. - Figure 2.42: Building in the vacuum insulation between the purenit battens………… - Figure 2.43: Aerogels in combination with glass Opaque nanogel pearls……………… - Figure 2.44: A dose-up of aerogel granulate. Glazing elements filled with aerogel…… - Figure 2.45: Glass sample with black edging and aerogel-filled glazing cavity……… - Figure 2.46: Country Zoo interior showing Nanogel glazing used in roof……………... - Figure 2.47: Nanogel glazing material used in roof…………………………………….. - Figure 2.48: Close-up of a phase change material embedded in glazing……………… - Figure 2.49: Layer composition of a decorative PCM gypsum plaster applied to a

masonry substrate…………………………………………………………………………... - Figure 2.50: "Sur Falveng" housing for elderly people interior………………………… - Figure 2.51: "Sur Falveng" housing for elderly people exterior façade……………… - Figure 2.52: Air-purifying curtain materials can simultaneously be equipped with

antibacterial properties……………………………………………………………………… - Figure 2.53: Air-purifying curtains across the width of this dance and work-out room

help maintain a better indoor air quality……………………………………………………. - Figure 2.54: Air-purifying materials such as plasterboard or acoustic panels…………..

23 24

24

24

25 26

26 27 27

28

28

28

28 29 29 29

30 30 31 31 32 33 33 34 34 34 35 35 35 36 36 37

37 38 38

39

39 40

VIII

- Figure 2.55: Photocatalytic pavement surfacing……………………………………… - Figure 2.56: Concrete paving panels with photocatalytic properties used as a design

element in a car park……………………………………………………………………… - Figure 2.57: Jubilee Church Exterior showing self-cleaning concret…………………… - Figure 2.58: Jubilee Church Exterior…………………………………………………… - Figure 2.59: Electrochromatic glass with an ultra-thin nanocoating needs only be

switched once to change state, gradually changing to a darkened yet transparent state. At present the maximum dimension of glazing panels is limited………………………………

- Figure 2.60: The gel fills material in the glazing cavity (here faulty but clearly visible) foams when exposed to fire for an extended period………………………………………

- Figure 2.61: A robust sandwich panel made of straw and hemp with a glassy coating that serves as a bonding agent and is also fire-resistant. When exposed to fire the product smoulders and extinguishes…………………………………………………………………

- Figure 2.62: Deutsche Post headquarters Exterior……………………………………… - Figure 2.63: Deutsche Post headquarters interior……………………………………….. - Figure 2.64: Deutsche Post headquarters fire safety glass……………………………… - Figure 2.65: Scratchproof varnishes are not able to withstand major damage, for

instance scratches from a key, but they can protect a car from scratching resulting from a car wash or from dirt and dust in transit. Layers of a protective varnish…………………...

- Figure 2.66: The control room of the new Baytubes® production facility in Laufenburg, showing the top of the fluidized bed reactor…………………………………

- Figure 2.67: Material price in US$/kg for common engineering materials and for typical Nanomaterials………………………………………………………………………

- Figure 2.68: The Kurakuen house in Nishinomya City, Japan, designed by Akira Sakamoto Architect and Associates, uses a photocatalytic self-cleaning paint—one of the many architectural products based on Nanomaterials………………………………………

- Figure 2.69: The evolution of arches that act primarily in compression only was related to the inherent material properties of masonry, which can carry large stresses in compression but little in tension…………………………………………………………….

- Figure 2.70: The introduction of materials such as steel that can carry bending stresses involving both tension and compressive stresses has allowed designers to explore new shapes………………………………………………………………………………………

- Figure 2.71: Primary material characteristics…………………………………………

- Figure 3.1: Recycling items for building………………………………………………… - Figure 3.2: Flow of CO2 in an ecosystem……………………………………………… - Figure 3.3: Helix of sustainability – the carbon cycle of manufacturing……………… - Figure 3.4: One way in which chemists manipulate carbon nanotubes is by creating

nanotubes derivatives nanotubes that are decorated with extra molecules that give the tubes unique properties or act as chemical "handles" for further manipulation……………

- Figure 3.5: Single-walled carbon nanotubes can be extruded to form macroscopic fibers………………………………………………………………………………………

- Figure 3.6: This image shows a single carbon nanotubes isolated and enclosed in a molecule……………………………………………………………………………………..

- Figure 3.7: The largest nanotube model in the world was produced by a team at Rice University in Houston, Texas……………………………………………………………….

- Figure 3.8: A perceptional 3D image of the proposed carbon tower by Peter Testa…… - Figure 3.9: Computer aided engineering design for Testa's carbon tower……………… - Figure 3.10: Computer aided engineering design for designing and forming carbon fiber

of Testa towers……………………………………………………………………………… - Figure 3.11: A longitudinal section of the Carbon Tower……………………………… - Figure 3.12: Working principle of a solar cell…………………………………………… - Figure 3.13: Thin-film Solar Cell………………………………………………………… - Figure 3.14: Nanoparticles produce the best solar cells…………………………………

40

40 41 41

42

43

43 44 44 44

45

46

47

48

48

48 49

55 55 56

58

58

58

59 60 60

61 61 63 64 64

IX

- Figure 3.15: Metal foil……………………………………………………………………. - Figure 3.16: Solar Cell Panel…………………………………………………………… - Figure 3.17: Nanosolar combines a host of innovations to deliver a distinct overall cost

reduction…………………………………………………………………………………… - Figure 3.18: Panel size drives balance-of-system cost savings on mounting labor and

panel-to-panel cabling………………………………………………………………………. - Figure 3.19: The Utopia One tower……………………………………………………… - Figure 3.20: 'utopia one' power, through Nano technology……………………………… - Figure 3.21: Interior View of Utopia One tower………………………………………… - Figure 3.22: A 3.8 cm (1.5 in) OLED display…………………………………………… - Figure 3.23: Structure of a typical bottom emitter OLED device……………………… - Figure 3.24: Schematic cross-sections of a Z-system (left), a T-system (middle) and a

clipping system (right)……………………………………………………………………… - Figure 3.25: Guidelines for OLED module pitches of 1.5M and multiples thereof…… - Figure 3.26: Basic geometric shapes…………………………………………………… - Figure 3.27: Four room models with different scenarios for comparative evaluation

placed next to each other. In this case the color temperature of light was altered which was subject of evaluation in another study………………………………………………………

- Figure 3.28: A nanosensor probe carrying a laser beam (blue) penetrates a living cell to detect the presence of a product indicating that the cell has been exposed to a cancer-causing substance……………………………………………………………………………

- Figure 3.29: Off the Grid: Sustainable Habitat 2020…………………………………… - Figure 3.30: The active skin of building moves and collect light to channel and generate

energy then control it with the grid without electricity…………………………………….. - Figure 3.31: The active skin of building reacts with wind to channel and generate energy

and filtering air and cooling it………………………………………………………………. - Figure 3.32: The active skin of building reacts to rains and collects water to be used in

closed loop………………………………………………………………………………… - Figure 3.33: The active skin of building collect humane waste to convert in biogas used

in heating, cooking and washing…………………………………………………………….

64 64

65

65 66 66 66 67 67

68 68 68

69

70 71

71

72

72

73

X

LIST OF ABBREVIATIONS

- AFM - ANI - CIGS - CNT - CVD - DNA - E-M - ECNT - FIB - GMOS - HCFCs and CFCs - Low voc - MNPS - MWNTs - NF - NM - NS - NT - OLED - PAS - SEM - STM - SWNTs - TiC - TiO2 - ULEHB - VQCs - Wt%

Atomic Force Microscopy. Applied Nanotech.

Copper, indium, gallium and selenium. Carbon Nano tubes.

Chemical Vapor Deposition. Deoxyribonucleic Acid.

Electromagnetic. Enzyme-coated carbon nanotubes biosensors.

Focused Ion Beam. Gated metal oxide sensors.

Hydro chlorofluorocarbons (HCFCs) and Chlorofluorocarbons (CFCs) are ozone-depleting substances that have historically been used as refrigerants and as blowing agents in the making of foam products.

A material that is low-voc emits low volumes of Volatile Organic Compounds, which are harmful to human health. VOCs are common in paints, primers, sealants, glues, and many other products containing chemicals.

Metal nanoparticles sensors.

Multi-Walled Nano tubes. Nanofarads (NF). Nanometer (NM).

Nanoscale (NS). Nanotechnology (NT).

Organic Light Emitting Diode. Photo-acoustic sensing system. Scanning Electron Microscopy. Scanning tunneling microscope.

Single-Walled Nano tubes. Tungsten Carbide. Titanium Dioxide.

Ultra Low Energy High Brightness Light. Volatile organic compounds.

The actual percentage by weight of nanotubes content.

XI

Nanomaterials & Architecture Research Structure Chart

• Introduction.•What's Nano?•Nanotechnology.•Nanotechnology and Architecture (NanoArchitecture).• The Future of Architecture with Nanotechnology.• Conclusion.

Nanotechnology

• Introduction.•Nanomaterials.•Nanomaterials Products and Benefits.•Nanomaterials Costs.•Nanomaterials in Architecture Design.• The Holistic Application of Nanosurfaces In Interiors.• Conclusion.

Nanomaterials Products

• Introduction.• Green Nanotechnology.•Nanomaterials in Sustainability and the Environment.•Nanomaterials in Sustainability and the Energy.• Conclusion.

Future Applications of Nanomaterials in Architecture for Sustainable development

Cha

pter

I

"Fun

dam

enta

l Kno

wle

dge"

Cha

pter

II

"The

oret

ical

Stu

dy"

Cha

pter

III

"App

licat

ions

"

General Conclusion & Recommendations

• Introduction and Research Objectives.

XII

INTRODUCTION

As people involved in construction, we are very familiar with the concept of getting raw materials, bringing them together in an organized way and then putting them together into a recognizable form. The finished product is a passive machine that does not change or adapt to the surroundings or environment. It works and slowly decays as it is used and abused by the environment and the owners of the project. Construction then is definitely not a new science or technology and yet it has undergone great changes over its history. The industry we see today is the result of a progression in science, technology, process and business. [8]

In the same vein, nanotechnology is not a new science and it is not a new technology either. It is rather an extension of the sciences and technologies that have already been in development for many years and it is the logical progression of the work that has been done to examine the nature of our world at ever smaller and smaller scale. [8]

There is currently an extraordinary amount of interest in Nanomaterials and nanotechnologies, terms now familiar not only to scientists, engineers, architects, and product designers but also to the general public. Nanomaterials and nanotechnologies have been developed as a consequence of truly significant recent advances in the material science community. [2]

Possibilities for the future are numerous. Nanotechnology may make it possible to manufacture lighter, stronger, and programmable materials that require less energy to produce than conventional materials, that produce less waste than with conventional manufacturing, and that promise greater fuel efficiency. [3]

What then does something like nanotechnology – a fundamentally high-tech endeavor, have to offer such an apparently low tech and conservative field such as construction? The fact is that construction deals with high-tech materials and processes that have been commoditized for use in the never-ending prototyping that is construction. For example, concrete and steel (together with its bolting and welding) are both high tech materials that are simple to use and there in lie their beauty. Materials and design therefore, is the first avenue through which nanotechnology can exert an influence. [8]

In the excitement surrounding these new materials and technologies, however, their potential can, and has been, frequently over hyped. A mystique surrounds these words that can cloud understanding of what Nanomaterials and nanotechnologies really are and what they can deliver. One of the purposes of this research is to demystify the subject and distinguish what is real from what is not. Though there is a need to better understand what benefits and costs might be associated with using Nanomaterials, in the design fields little true understanding exists about what these new materials and technologies actually are and how they might be used effectively. [2]

Nanomaterials are materials made from nanometer-scale substances has opened up possibilities for new and innovative functions. They can be used as coatings, insulations, air purifying or in product manufacture. Privacy, sustainability, and security are just a few of the issues that will be profoundly affected by Nanotechnology and Nanomaterials. Nanomaterials will help in reducing CO2 emission by new ways and this will reflect in environment, humane and society.

XIII

RESEARCH OBJECTIVES

1- To meet these aspirations, the scope of the research is inherently large, seeking to explore what Nanomaterials and nanotechnologies are and how they might be applied in Architecture. [2]

2- A broad knowledge of resulting properties is important, too, for any designer or engineer trying to use Nanomaterials. [2]

3- Know the positive benefits of Nanomaterials in architecture and it's applied on environment and sustainable architecture.

4- Nanotechnology uses such novel materials and techniques to offer innovative products, cost saving productive processes, and environmental remediation. [22]

5- Identifying Nanomaterials from its types, properties and uses in architecture.

6- Explain the important role of science and advanced technology in presenting new developed materials will participate in providing architectural solutions for many problems in 21th century.

Chapter One

Nanotechnology

1.1. Introduction. 1.2. What's Nano? 1.3. Nanotechnology. 1.4. Nanotechnology and Architecture (NanoArchitecture). 1.5. The Future of Architecture with Nanotechnology. 1.6. Conclusion.

Chapter One Nanotechnology

1

1. Nanotechnology

1.1. Introduction:

The term “nanotechnology” refers to the study, design, synthesis, manipulation, and application of materials, devices and functional systems by controlling matter at the nanoscale. These new, atomically precise structures, such as carbon nanotubes or minuscule instruments to examine the inside of the human body, promise a new technological revolution still difficult to imagine. [3]

(Advanced technology and Sustainability), Nanotechnology is an exciting area of scientific development which promises ‘more for less’. It offers ways to create smaller, cheaper, lighter and faster devices that can do more and cleverer things, use less raw materials and consume less energy (Sustainable Environment). There are many examples of the application of nanotechnology from the simple to the complex. For example, there are Nano coatings which can repel dirt and reduce the need for harmful cleaning agents, or prevent the spread of hospital-borne infections. [21]

In contrast to recent engineering efforts, nature developed “Nanotechnologies” over billions of

years, employing enzymes and catalysts to organize with exquisite precision different kinds of atoms and molecules into complex microscopic structures that make life possible. These natural products are built with great efficiency and have impressive capabilities, such as: [3]

There are two principal reasons for qualitative differences in material behavior at the

nanoscale: [3] 1- Quantum mechanical effects come into play at very small dimensions and lead to new

physics and chemistry (biotechnology). 2- A defining feature at the nanoscale is the very large surface-to-volume ratio of these

structures (biotechnology). The “Nanoscale” (see Figure 1.1) is typically measured in nanometers, or billionths of a

meter, and materials built at this scale often exhibit distinctive physical and chemical properties due to quantum mechanical effects. Techniques for working at the nanoscale have become essential to electronic engineering, and nanoengineered materials have begun to appear in consumer products. For example, billions of microscopic “nanowhiskers,” each about 10 nanometers in length, have been molecularly hooked onto natural and synthetic fibers to impart

Figure 1.1: Examples from biological andmechanical realms illustrate various “orders ofmagnitude” (powers of 10), from 10−2 meter downto 10−7 meter.

1- The power to harvest solar energy, to convert minerals. 2- Water into living cells, to store and process massive amounts of data using large

arrays of nerve cells. 3- To replicate perfectly billions of bits of information stored in molecules of

deoxyribonucleic acid (DNA).


2

stain resistance to clothing and other fabrics; zinc oxide nanocrystals have been used to create invisible sunscreens that block ultraviolet light; and silver nanocrystals have been embedded in bandages to kill bacteria and prevent infection.[3]

When introducing new technologies to a field such as the construction industry, one should always first examine the benefits it can bring and its effect on sustainable development. In the case of the application of nanotechnology we are talking about: [1]

• Added value. • Additional functionality. • Market demand with regard to product

development. • Good design in principle is always based

on demand, and in this way contributes to the evolution of both Nanomaterials and the resulting nanoproducts (see Figure 1.2).

In the long term the materials and products for which there is a demand will become established whereas others will disappear from the market. The use of nanotechnology is therefore not an end in itself but follows an ongoing demand for innovation - as such it can also be a marketing factor Independent of marketing factors (Economic Sustainability), nanotechnology can make a concrete contribution to the following areas: [1]

• Optimization of existing products. • Damage protection. • Reduction in weight and / or volume. • Reduction in the number of production stages. • A more efficient use of materials. • Reduced need for maintenance (easy to clean, longer cleaning intervals) and / or

operational upkeep.

Figure 1.2: NanoHouse Show the good design andbenefits of using Nanomaterials. [43]

Sust

aina

ble

Dev

elop

men

t

• And as a direct result: • Reduction in the consumption of raw materials and energy and reduced CO2

emissions that will affect good in environment. • Conservation of resources. • Greater economy. • Comfort.


3

1.2. What's Nano? [12]

Nano (symbol n) is a prefix in the International System of Units denoting a factor of 10−9. It is frequently encountered in science and electronics for prefixing units of time and length, like 30 nanoseconds (symbol ns), 100 nanometers (nm) or in the case of electrical capacitance, 100 nanofarads (nF).

The prefix is derived from the Greek νᾶνος, meaning dwarf, and was officially confirmed as standard in 1960.

In the United States, the use of the Nano prefix for the farad unit of electrical capacitance is uncommon; capacitors of that size are more often expressed in terms of a small fraction of a microfarad or a large number of picofarads.

When used as a prefix for something other than a unit of measure, as in "nanoscience", Nano means relating to nanotechnology, or on a scale of nanometers.

1.2.1. A virtual discovery journey into the worlds of micro and Nano cosmos: [13]

"Nano-journeys" whisk you away to micro and Nano cosmos. On various route you can gradually "shrink yourself" into worlds invisible to us and penetrate into the smallest known dimensions of our universe (see Figure 1.3).

The route described here is the so-called "Ego-trip (an act undertaken to increase your own power and influence or to draw attention to your own importance for something "Nano")".

Figure 1.3: "Nano‐journeys ‐ adventures beyond the decimal" provides a virtual journey of discovery into the minute worlds of the micro‐ and nanocosmos.


4

1.3. Nanotechnology (NT):

1.3.1. Definition: [14]

Nanotechnology, shortened to "nanotech", is the study of the control of matter on an atomic and molecular scale. Generally nanotechnology deals with structures of the size 100 nanometers or smaller in at least one dimension, and involves developing materials or devices within that size. Nanotechnology is very diverse, ranging from extensions of conventional device physics to completely new approaches based upon molecular self-assembly, from developing new materials with dimensions on the nanoscale to investigating whether we can directly control matter on the atomic scale.

Nanotechnology and environment: There has been much debate on the future implications of nanotechnology. Nanotechnology has the potential to create many new materials and devices with a vast range of applications, such as in medicine, electronics and energy production. On the other hand, nanotechnology raises many of the same issues as with any introduction of new technology, including concerns about the toxicity and environmental impact of Nanomaterials, and their potential effects on global economics, as well as speculation about various doomsday scenarios.

1.3.2. Origins: [14]

• The first use of the concepts found in 'Nano-technology' was in "There's Plenty of Room at the Bottom", a talk given by physicist Richard Feynman at an American Physical Society meeting at Caltech on December 29, 1959. Feynman described a process by which the ability to manipulate individual atoms and molecules might be developed, using one set of precise tools to build and operate another proportionally smaller set, and so on down to the needed scale.

• The term "nanotechnology" was defined by Tokyo Science University Professor Norio Taniguchi in a 1974 paper as follows: "'Nano-technology' mainly consists of the processing of, separation, consolidation, and deformation of materials by one atom or by one molecule."

• In the 1980s the basic idea of this definition was explored in much more depth by Dr. K. Eric Drexler, who promoted the technological significance of Nanoscale phenomena and devices through speeches and the books Engines of Creation: The Coming Era of Nanotechnology (1986) and Nanosystems: Molecular Machinery, Manufacturing, and Computation, and so the term acquired its current sense. Engines of Creation: The Coming Era of Nanotechnology is considered the first book on the topic of nanotechnology.

• Nanotechnology and nanoscience got started in the early 1980s with two major developments; 1- the birth of cluster science, 2- the invention of the scanning tunneling microscope (STM). This development led to the discovery of fullerenes (see Figure 1.4) in 1985 and carbon nanotubes a few years later.

Figure 1.4: Buckminster fullerene C60, also knownas the buckyball, is the simplest of the carbonstructures known as fullerenes. Members of thefullerene family are a major subject of researchfalling under the nanotechnology umbrella.


5

• In another development, the synthesis and properties of semiconductor nanocrystals was studied; this led to a fast increasing number of metal and metal oxide nanoparticles and quantum dots. The atomic force microscope was invented six years after the STM was invented.

• In 2000, the United States National Nanotechnology Initiative was founded to coordinate Federal Nanotechnology research and development.

1.3.3. Fundamental concepts: [14]

• Scale: One nanometer (nm) is one billionth, or 10−9 of a meter. By comparison, typical carbon-carbon bond lengths, or the spacing between these atoms in a molecule, are in the range 0.12–0.15 nm, and a DNA double-helix has a diameter around 2 nm. On the other hand, the smallest cellular life-forms, the bacteria of the genus Mycoplasma, are around 200 nm in length.

• To put that scale in another context, the comparative size of a nanometer to a meter is the same as that of a marble to the size of the earth. Or another way of putting it: a nanometer is the amount a man's beard grows in the time it takes him to raise the razor to his face.

• Two main approaches are used in Nanotechnology:

1- In the "Bottom-Up" approach, materials and devices are built from molecular components which assemble themselves chemically by principles of molecular recognition (see Figure 1.5).

2- In the "Top-Down" approach, Nano-objects are constructed from larger entities without atomic-level control (see Figure 1.6).

Areas of physics such as nanoelectronics, nanomechanics and nanophotonics have evolved during the last few decades to provide a basic scientific foundation of Nanotechnology.

Figure 1.5: Sarfus image of a DNA biochipelaborated by bottom‐up approach.

Figure 1.6: This device transfers energy from Nanothin layers of quantum wells to nanocrystals abovethem, causing the nanocrystals to emit visible light.


6

1.4. Nanotechnology and Architecture (NanoArchitecture):

With building construction and operation estimated to be a trillion dollar per year industry worldwide it is to be expected that Nanomaterials and nanotechnology will play an increasing role in the construction industry. According to nanowerk “dozens of building materials incorporate nanotechnology, from self-cleaning windows to flexible solar panels to Wi-Fi blocking paint,” and “many more are in development, including self-healing concrete, materials to block ultraviolet and infrared radiation, smog-eating coatings and light-emitting walls and ceilings.” Examples are: [18]

1. Carbonfiber (see Figure 1.7). 2. Energycoating. 3. Heat absorbing windows, (Also for heat

absorbing windows). 4. Nanocoatings, such as Nanoprotect

Glass,Nanoprotect CS,Nano Protex,NanosealWood,and, Nanoprotect Metal.

5. INSULADD,® QuantumSpheres,andNano aluminium powders.

6. Ultra Low Energy High Brightness Light (ULEHB).

7. Nanosensors.

Some of this will be illustrated in next chapters and this is a brief illustration about two examples in Nanotechnology:

1- Ultra Low Energy High Brightness Light :

lighting will produce the same quality light as the best 100 watt light bulb (Sustainable Energy), but using only a fraction of the energy and last many times longer. [18]

Imagine changing the color of your walls and ceilings to fit your mood. That's what researchers at the University of Surrey hope to achieve with solid state lighting devices using Nano-composite materials. [28]

These new ultra low energy lighting devices will be fabricated using carbon nanotube-organic composites which will significantly reduce energy running costs, thus reducing carbon dioxide emissions at power generating stations (Sustainable Environment).

Potential uses such as variable mood lighting over a whole wall or ceiling opens up a range of exciting applications (see Figure 1.8). ULEHB is also expected to have wide uses in signage, displays, street lighting, commercial lighting, public buildings and offices. [28]

Figure 1.8: Variable mood lighting over a whole wall.

Figure 1.7: The entire facade of the Nano tower isfaceted, inspired by a Nano scale carbon tube. [42]


7

2- Nanosensors:

Which can monitor temperature, humidity, and airborne toxins, vibration, decay and other performance concerns in building components, from structural members to appliances, will be increasingly incorporated in the planning of building components, and many buildings and structures will be retrofitted with nanosensors.

After the bridge collapse in Minneapolis, USA it is to be expected that bridges will be retrofitted with nanosensors and that new bridges will have nanosensors incorporated from the beginning. In 2006, Applied Nanotech (ANI) presented carbon monoxide and carbon dioxide devices and a hydrogen sensor for power transformers, gated metal oxide sensors (GMOS), photo-acoustic sensing system (PAS), metal nanoparticles sensors (MNPS), and enzyme-coated carbon nanotubes biosensors (ECNT). [18]

Nanotechnology in Construction is a new Freedonia industry study that provides recent historical data and forecasts to 2011, 2016 and 2025 by product, application and market. It also presents information on industry participants, including companies, government agencies and laboratories, and universities with Nanomaterials research and development activities. On Elvins small plan, one finds diagram which highlights some relationship of nanotechnology to construction (see Figure 1.9). [18]

The Nano Vent-Skin (see Figure 1.10) is a zero-emission material that takes a tri-partite approach towards energy efficiency. First, it soaks up sunlight via a photovoltaic layer, and transfers energy via Nano-wires (see Figure 1.11) to storage units at the end of each panel. Second, its tiny turbines employ “polarized organisms” to create chemical reactions, generating power each time the turbine makes contact with the structure. Third, the organisms present in the inner skin of each turbine soak up C02. [44]

Figure 1.9: Relationship of nanotechnology to construction.

Figure 1.10: Nano Vent‐Skin exterior.

Figure 1.11: Nano‐structure components.


8

1.5. The Future of Architecture With Nanotechnology:

How architects can design with the emergence of nanotechnology? The future of architecture is in development today – and such architects like John M. Johansen are creating unique perspectives on how we will fuse new technologies with build form. [20]

In the early stages of molecular growth processes, small molecules survive only in a sealed vat where an entactic environment is assured. However, it is likely that these perishable protein molecules will build larger, more durable molecules that will withstand and survive in the external environment. This growth, development from simple to complex molecules, from inside to outside the vat, is the critical and essential assumption of my proposal. It is only in this way that the production of large products can be realized. [5]

He brings up a few very important points about what Nanoarchitecture can bring. Here are some key ideas… [20]

1.5.1. Making the Technology More Humane: [20]

Johansen’s vision for the future of architecture is quite thought-provoking. You get a sense of how built environments can evolve — for the better. Johansen’s envisioned “community” shows a new kind of architecture that makes use of the emergence of nanotechnology in both adaptive and humane ways.

Nanoarchitecture will allow for designs that better interact with the human senses. Experiencing this type of architecture could feel more “natural” and less forced than many of the designs we experience today (see Figure 1.12).

Johansen shows that the future of architecture can be both technologically rich and humane simultaneously.

1.5.2. Designing Your Own Materials:

By merging both nanotechnology and architecture, the advent of nanotechnology will give architects renewed freedoms that we don’t experience today. For instance, the ability to design your own materials going beyond wood, concrete and glass (see Figure 1.13).[20]

Figure 1.12: Community center.

Figure 1.13: The molecule design of communitycenter.


9

1.5.3. Buildings That Will “Grow”:

It is interesting to think of architecture as a “growing” environment that evolves according to different respective codes. Nanoarchitecture could treat such codes (or rules) as a way to optimize intended functions and aesthetics. Architecture would then be more of a dynamic entity, morphing to occupant needs (see Figure 1.14). [20]

In future years, if we cannot find a buyer for our house, we will demolish it, or more correctly, the house will demolish itself. The building growth operations will be recycled for future buildings. [5]

We may fairly assume that the molecular growth processes, though more extensive in this case, are the same as for the Molecular-Engineered House. From vats at the building site, root, stalk, branch, platform, lattice, membrane, and opening develop. Light control, self-cleaning, repairs and demolition systems also emerge (see Figure 1.15). [5]

1.5.4. Responsive Architecture: [20]

An architecture that is responsive would allow for better design variations that meet occupant need. Personalization of Nanoarchitectural spaces will be a likely benefit giving occupants greater flexibility and choice.

1.5.5. Bringing Architecture Closer to Nature:

Johansen’s vision of a chapel responding to light energy is a rather beautiful idea. This one concept powerfully illustrates the possibilities that Nanoarchitecture will allow. It is likely that Nanoarchitecture will bring architectural design a few steps closer to having buildings more synchronously harmonize with nature (see Figure 1.16).[20]

This idea resembles the target of sustainable development.

Figure 1.14: Diagrams of the days of constructionof the molecular‐engineered house.

Figure 1.15: The Multistory growth building.

Figure 1.16: The sun Chapel, morphable structure responding to light energy following the passage of the day.


10

Another visionary example of how the architecture integrating with nature listed here it is Molecular-Engineered House for the year 2000, 2200. The following is a diary created by the owner of a molecular-engineered house written during its construction. It is set in the year 2200. [5]

Day 1: Excavation begins on site where assembly vats will be placed.

Day 2: vats delivered to building site, along with selected chemicals and bulk materials in liquid form. The various materials are then pumped into the vats.

Day 3: The code developed from an architect‘s designs and then engineering and molecularly modeled, is ceremonially placed in the vat. We are amused that this code represents what long ago were the drawings, specifications, and strategies of construction management.

Day 4: Molecular growth, in the form of a vascular system, begins. This starts with roots stemming from the chemical composite. Reaching up and out of the vat to ground level, the roots form rudimentary ―grade beams ―extending horizontally to the edge of the house, where they curve upward to support the superstructure. Cross ribs connect the grade beams and form the ground floor platform.

Day 5: The cross of the superstructure starts with the development of primary exterior and interior vertical ribs (see Figure 1.18). The infill of minor connecting ribs— "the lattice" —also begins to develop. The lattices are of varied densities, and are programmed to meet stress requirements—being less dense and more open in pattern where door openings are specified, for example. Fine web work a membranes appear as protective enclosures an interior partitioning. A neural net work communicating via transmissions—and not preprogrammed—couples to the vascular system and begins operation.

Day 6: The upper platforms, supported by lateral brackets stemming from some the major structural ribs, are accessibly by a sprouting central spiral staircase. Exterior protective membranes conceal the interior. The molecules of the membranes link to create an unbroken fabric. The membranes provide openings for accesses that are prompted by two molecular activates first, the membranes are infused with electric current by a manual selector that induces the molecules to disengage and form the openings. Second, other molecules, acting as muscles at the opening edge, flex to draw the exterior membrane apart. We enter our house.

Day 7: For the first time, we experience the space, ample for a small house. Ethereal light glows through the translucent membranes. With a signal, these membranes change from translucent to opaque to transparent, providing a view anywhere at any time desired. Our house is self-sufficient, functioning without dependence upon any outside public services. Solar power activates

Figure 1.17: The natural walls of the Molecularengineered future house.

Figure 1.18: A Plan and longitudinal section of theGrowing molecular‐engineered house.


11

heating, cooling, recycling of wastes, and purifying of water. The vats and vascular system, vital to the growth of our house, remain and will convey additional material when repair or replacement is required.

Interior finishes grow around us. "Body support," known previously as sofas, chairs, tables, and beds, are springing up from the floor, out from the wall ribs, and hanging from the arched vault –furniture as an extension of the structure itself. The floor, a "morphable topographic carpet," consists of resilient, molecular, spongy substance that is responsive to our every comfort, whim, or tactile experience.

Day 8: We return the next day to find our house more familiar. As a like "light modulator," the membrane responds to ever-changing conditions of the immediate environment to appear as cloudy, opalescent, gossamer, iridescent, and opaque. We have created an artificial, organic, protective cocoon.

Day 9: After six days of molecular growth, we move in. the house anticipates our changing needs, expanding the living space to form a small study, repartitioning the master bedrooms, rearranging and redesigned the "body supports," and extending the wheeled legs to a new site. These shape changes demonstrate the flexibility of the molecular engineering.

In future years, if we cannot find a buyer for our house, we will demolish it, or more correctly, the house will demolish itself. The building growth operations will be recycled for future buildings.

Figure 1.19: Exterior view of the Molecularengineered future house.

Figure 1.20: Diagrams of the days of construction ofthe molecular‐engineered house.


12

1.6. Conclusion:

1- Nanotechnology has been around for two decades, but the first wave of applications is only now beginning to break. As it does, it will affect everything from the batteries we use to the pants we wear to the way we treat cancer. [24]

2- Green Nanotechnology producing Nanomaterials and products without harming the environment or human health, and producing Nano-products that provides solutions to environmental problems (Sustainable NanoArchitecture). [25]

3- Green Nanotechnology is the development of clean technologies, "to minimize potential environmental and human health risks associated with the manufacture and use of Nanotechnology products, and to encourage replacement of existing products with new Nano-products that are more environmentally friendly throughout their lifecycle (Sustainable Environment). [25]

4- Carbon has proved a useful element in Nanotechnology. One of the science's building blocks is a molecule that contains 60 carbon atoms arranged in a sphere. A molecule of C60 looks like the geodesic dome invented by Buckminster Fuller, thus its nickname: buckyball. [24]

5- By merging both Nanotechnology and Architecture, the advent of Nanotechnology will give architects renewed freedoms on advanced principles (advanced technology + advanced science) that we don’t experience today. [20]

Chapter Two

Nanomaterials Products

2.1. Introduction. 2.2. Nanomaterials. 2.3. Nanomaterials Products and Benefits. 2.4. Nanomaterials Costs. 2.5. Nanomaterials in Architecture Design. 2.6. The Holistic Application of Nanosurfaces in Interiors. 2.7. Conclusion.

Chapter Two Nanomaterials Products

13

2. Nanomaterials Products

2.1. Introduction:

There are many fascinating examples of Nanotechnology applications in new materials. For example, polymer coatings are notoriously easily damaged, and affected by heat. Adding only 2% of nanoparticulate clay minerals to a polymer coating makes a dramatic difference, resulting in coatings that are tough, durable and scratch resistant. This has implications for situations where a material fits a particular application in terms of its weight and strength, but needs protection from an external, potentially corrosive environment - which a reinforced polymer nanocoating can provide. Other nanocoatings can prevent the adherence of graffiti, enabling them to be easily removed by hosing with water once the coating has been applied. This has the important knock-on effect of improving urban environments, making them more attractive to bona fide citizens and less encouraging to criminals. [22]

In architecture two fundamentally different design approaches prevail when dealing with

materials and surfaces: [1]

1- Honesty of Materials – “what you see is what you get”:[1]

This approach is favored by those architects for whom authenticity is a priority and who value high-quality materials such as natural stone or solid woods.

2- Fakes – artificial surfaces that imitate natural materials:[1]

For the most part, fake materials are chosen for cost reasons. Wood, whether in the form of veneer or synthetic wood-effect plastics, is considerably cheaper than solid wood. Even concrete or venerable walls can be had in plastic. Artificial surfaces are brought to perfection the grain can be tailored to appear exactly as desired; the color matches the sample precisely and does not change over the course of time. More and more ―patinated surfaces are being created that exhibit artificial aging: instant patinas precisely controllable. Certain design approaches prefer the provocation of deliberate artificiality.

In future, a third option will be available:

3- Functional Nanosurfaces, emancipated from underlying materials:[1]

The properties of such ultra-thin surfaces can differ entirely from the material they enclose and can be transparent and completely invisible. Also possible are nanocomposites with new properties: Nanoparticles or other Nanomaterials are integrated into conventional materials so that the characteristics of the original material are not only improved but can be accorded new functional properties or even be made multifunctional. Surface materials that are customized to have specific functional properties are set to become the norm, heralding a switch from catalogue materials to made-to-measure materials with definable combination of properties – a perfectly modular system.

Nanomaterials also make excellent filters for trapping heavy metals and other pollutants

from industrial wastewater (Sustainable Environment). One of the greatest potential impacts of Nanotechnology on the lives of the majority of people on Earth will be in the area of economical water desalination and purification. Nanomaterials will very likely find important use in fuel cells, bioconversion for energy, bioprocessing of food products, waste remediation, and pollution. [3]


14

2.2. Nanomaterials:

Nanomaterials are a field which takes a materials science-based approach to

Nanotechnology. It studies materials with morphological features on the nanoscale, and

especially those which have special properties stemming from their nanoscale dimensions. Nanoscale is usually defined as smaller than a one tenth of a micrometer in at least one dimension, though this term is sometimes also used for materials smaller than one micrometer. [15]

A Nanomaterial is an object that has at least one dimension in nanometer scale. Nanomaterials are categorized according to their dimensions (see Figure 2.1). [11]

2.2.1. Background: [15]

An aspect of nanotechnology is the vastly increased ratio of surface area to volume present in many nanoscale materials which makes possible new quantum mechanical effects, for example the “quantum size effect” where the electronic properties of solids are altered with great reductions in particle size.

Nanotechnology can be thought of as extensions of traditional disciplines towards the explicit consideration of these properties. Additionally, traditional disciplines can be re-interpreted as specific applications of nanotechnology. This dynamic reciprocation of ideas and concepts contributes to the modern understanding of the field. Broadly speaking, Nanotechnology is the synthesis and application of ideas from science and engineering towards the understanding and production of novel materials and devices. These products generally make copious use of physical properties associated with small scales.

Materials reduced to the nanoscale can suddenly show very different properties

compared to what they exhibit on a macroscale, enabling unique applications. For instance, opaque substances become transparent (copper); inert materials attain catalytic properties (platinum); stable materials turn combustible (aluminum); solids turn into liquids at room temperature (gold); insulators become conductors (silicon). Materials such as gold, which is chemically inert at normal scales, can serve as a potent chemical catalyst at nanoscales. Much of the fascination with nanotechnology stems from these unique quantum and surface phenomena that matter exhibits at the nanoscale.

Figure 2.1: Nanomaterials categorized based on their dimensions.


15

2.2.2. Scale: [2]

As discussed in the previous Chapter, Nano stands for nanometer, one billionth (10−9

) of a

meter. This defines a length scale that is, for these materials, important in some way,

influencing their mechanical, thermal, electrical, magnetic, optical, and aesthetic properties.

If you ask: What is the smallest particle in matter? Most people would reply: an atom. Atoms have a diameter of about one tenth of a nanometer. Atoms are themselves made up of units that can sometimes be thought of as particles: electrons, neutrons, and protons. They are much smaller, about 10−15 meters (a femtometer) in diameter, but when things get these small quantum-mechanical effects make them fuzzy, their size ill defined, so we shall stop there.

What is the other extreme? It used to be of global scale (“the ends of the Earth,” “poles apart”), but space exploration has changed all that, enlarging the concept of scale to intergalactic dimensions: light-years, just under 10,000,000 million km (1016 meters, 10 pentameters).

Figure 2.2 _ shows this wide range, from a femtometer at the bottom to 100 light-years on the top. It is the one from which perception expands, one that is built into our language. At the lower end the diameter of a hair (“it missed by a hair’s breadth”). The inch, originally the ell, is the length of the lower joint of the thumb. The foot is, well, the foot. A yard is a pace. A furlong is the length of a furrow, a league (about 5 km) is the distance a man or a horse can walk in an hour; thus 7-league boots take you a day’s journey at one step. Perhaps that is why these are called Imperial units. You would not design anything using units like these (although NASA apparently still does).

Figure 2.2: Length scales ranging from the subatomic through molecular, human, and terrestrial to

astronomic. The Nano range is shown on the lower right.


16

It was France, a nation that has contributed so much to rational thinking that gave us a system with some sense in it. The National Assembly of the First Republic, by decree in 1790, created the standards of length, volume, and weight that we know today as the metric system.

We live in a world in which everyday objects have a

size—we shall call it scale and give it the symbol L, for

length—in the range of millimeters to meters. Scale has a

profound effect on the behavior of structures made from

materials. This is an example of scale-dependent

mechanical response.

Most of the useful properties—stiffness, strength, thermal and electrical conductivities,

magnetism—come from the inside of atoms. At the familiar macroscale, the fraction of atoms that lie in the surface is minuscule. At the micron scale it is still tiny. But approach the nanoscale and it takes off (see Figure 2.3). The combination of small scale and a large fraction of “surface” atoms give a property set that can be very different from that of the bulk. It is only now being unveiled.

Nanomaterials have different mechanical, thermal, electrical, magnetic, optical, and, above all, chemical properties than those of the bulk. They can offer strong, wear-resistant coatings; they can change the ways in which heat and electricity are conducted; they have the ability, through their electrical and magnetic behavior, to store information and via their chemical behavior to catalyze chemical reactions, distribute drugs in the human body, and much more.

2.2.3. Structure Dimensions:

It is the structural length of the material that determines this: the finer the structure, the

shorter is the mean-free path and the higher the resistance. Magnetism involves domains of locally aligned magnetic moments; the domain boundaries have a characteristic thickness, again of atomic or nanodimensions. Optical properties, particularly, involve scattering or diffraction, both with specific length scales. Strength, too, is influenced by structural scale. [2]

If we can engineer the structural scale of a material (as particles, thin layers, or the crystal

size in bulk materials) in the right way, we can influence or interact with the property length

scale and thus manipulate the property itself. [2]

2.2.3.1. Nanoscale in One Dimension: [40]

A- Thin films, layers and surfaces:

One-dimensional Nanomaterials, such as thin films (see Figure 2.4) and engineered surfaces, have been developed and used for decades in fields such as electronic device manufacture, chemistry and engineering. In the silicon integrated-circuit industry, for example, many devices rely on thin films for their operation, and control of film thicknesses approaching the atomic level is routine. Advances are being made in the control of the composition and smoothness of surfaces, and the growth of films.

Figure 2.3: The fraction of atoms that lie in

the surface or internal interfaces of a

nanoscale or nanostructured material,

expressed as a percentage (%).

Figure 2.4: Thin Solar film.


17

Engineered surfaces with tailored properties such as large surface area or specific reactivity are used routinely in a range of applications such as in fuel cells and catalysts. The large surface area provided by nanoparticles, together with their ability to self assemble on a support surface, could be of use in all of these applications.

2.2.3.2. Nanoscale in Two Dimensions: [40]

Two dimensional Nanomaterials such as tubes and wires have generated considerable

interest among the scientific community in recent years. In particular, their novel electrical

and mechanical properties are the subject of intense research.

A- Carbon Nanotubes:

Carbon nanotubes (CNTs) were first observed by Sumio Iijima in 1991. CNTs are extended tubes of rolled graphene sheets (see Figure 2.5). There are two types of

CNT: single-walled (one tube) or multi-walled (several

concentric tubes). Both of these are typically a few

nanometers in diameter and several micrometers to

centimeters long. CNTs have assumed an important role in the context of Nanomaterials, because of their novel chemical and physical properties. They are

mechanically very strong, flexible (about their axis),

and can conduct electricity extremely well (the helicity of the graphene sheet determines whether the CNT is a semiconductor or metallic). All of these remarkable properties give CNTs a range of potential applications: for example, in reinforced composites, sensors, nanoelectronics and display devices.

B- Nanowires:

Nanowires are ultrafine wires or linear arrays of

dots, formed by self-assembly. They can be made from a wide range of materials. Semiconductor nanowires made of silicon (see Figure 2.6); gallium nitride and indium phosphide has demonstrated remarkable optical, electronic and magnetic characteristics (for example, silica nanowires can bend light around very tight corners).

Nanowires have potential applications in high-

density data storage; either as magnetic read heads or

as patterned storage media, and electronic and opto-

electronic nanodevices, for metallic interconnects of

quantum devices and nanodevices.

The preparation of these nanowires relies on sophisticated growth techniques, which include self assembly processes, where atoms arrange themselves naturally on stepped surfaces. The ‘molecular beams’ are typically from thermally evaporated elemental sources.

Figure 2.5: Image of Carbon Nanotubes structure.

Figure 2.6: Silica Nanowire.


18

2.2.3.3. Nanoscale in Three Dimensions: [40]

A- Nanoparticles:

Nanoparticles are often defined as particles of less

than 100nm in diameter (see Figure 2.7). We classify nanoparticles to be particles less than 100nm in diameter that exhibit new or enhanced size-dependent properties compared with larger particles of the same material. Nanoparticles exist widely in the natural world: for example as the products of photochemical and volcanic activity, and created by plants and algae. They have also been created for thousands of years as products of combustion and food cooking, and more recently from vehicle exhausts. Deliberately manufactured nanoparticles, such as metal oxides, are by comparison in the minority.

Nanoparticles are of interest because of the new properties (such as chemical reactivity and optical behavior) that they exhibit compared with larger particles of the same materials. For example, titanium dioxide and zinc oxide become transparent at the nanoscale, however are able to absorb and reflect UV light, and have found application in sunscreens. Nanoparticles have a range

of potential applications: in the short-term in new cosmetics, textiles and paints; in the longer

term, in methods of targeted drug delivery where they could be to used deliver drugs to a

specific site in the body.

Manufactured nanoparticles are typically not products in their own right, but generally serve as raw materials, ingredients or additives in existing products. For most applications, nanoparticles will be fixed (for example, attached to a surface or within in a composite) although in others they will be free or suspended in fluid. Whether they are fixed or free will have a significant effect on their potential health, safety and environmental impacts.

B- Fullerenes (carbon 60):

In the mid-1980s a new class of carbon material was discovered called carbon 60 (C60).Harry Kroto and Richard Smalley, the experimental chemists who discovered C60 named it "buckminsterfullerene", in recognition of the architect Buckminster Fuller, who was well-known for building geodesic domes, and the term fullerenes was then given to any closed carbon cage.

C60 are spherical molecules about 1nm in

diameter, comprising 60 carbon atoms arranged as 20

hexagons and 12 pentagons: the configuration of a

football (see Figure 2.8). In 1990, a technique to produce larger quantities of C60 was developed by resistively heating graphite rods in a helium atmosphere. Several applications are envisaged for fullerenes, such as miniature ‘ball bearings’ to lubricate surfaces, drug delivery vehicles and in electronic circuits.

Figure 2.7: Microscopic image of Nanoparticle.

Figure 2.8: C60 spherical molecules.


19

2.2.4. Classification: [15]

Materials referred to as "Nanomaterials" generally fall into two categories: Fullerenes

and Inorganic Nanoparticles.

2.2.4.1. Fullerenes: [15] [16]

The fullerenes are a class of allotropes of carbon

which conceptually are graphene sheets rolled into tubes or

spheres. These include the carbon nanotubes (or silicon nanotubes) which are of interest both because of:

• Their mechanical strength • Their electrical properties.

In April 2003, fullerenes were under study for potential medicinal use: binding specific antibiotics to the structure of

resistant bacteria and even target certain types of cancer cells

such as melanoma. The October 2005 issue of Chemistry and Biology contains an article describing the use of fullerenes as

light-activated antimicrobial agents. In the field of nanotechnology: heat resistance and superconductivity are among the properties attracting intense research.

There are many calculations that have been done using ab-initio Quantum Methods applied to fullerenes. By DFT (see Figure 2.9) and TDDFT methods one can obtain IR, Raman and UV spectra. Results of such calculations can be compared with experimental results.

2.2.4.2. Inorganic Nanoparticles: [15] [17]

Nanoparticles or nanocrystals made of metals, semiconductors, or oxides are of particular interest for their mechanical, electrical, magnetic, optical, chemical and other properties. Nanoparticles have been used as quantum dots and as chemical catalysts.

Nanoparticles are of great scientific interest as they

are effectively a bridge between bulk materials and atomic or

molecular structures. A bulk material should have constant physical properties regardless of its size, but at the Nano-scale

this is often not the case. Size-dependent properties are observed such as quantum confinement in semiconductor particles, surface Plasmon resonance in some metal particles and superparamagnetism in magnetic materials (see Figure 2.10).

Nanoparticles exhibit a number of special properties relative to bulk material. For example, the bending of bulk copper (wire, ribbon, etc.) occurs with movement of copper atoms/clusters at about the 50 nm scale. Copper nanoparticles smaller than 50 nm are considered super hard materials that do not exhibit the same malleability and ductility as bulk copper. The change in properties is not always desirable.

Figure 2.9: C60 with isosurface of ground

state electron density as calculated with

DFT.

Figure 2.10: TEM (a, b, and c) images of

prepared mesoporous silica nanoparticles

with mean outer diameter: (a) 20nm, (b)

45nm, and (c) 80nm. SEM (d) image

corresponding to (b). The insets are a high

magnification of mesoporous silica

particle.


20

2.3. Nanomaterials Products and Benefits:

By far the most compelling argument for using Nanotechnology in architecture is for

greater energy efficiency (Sustainable Environment). Nanotechnology offers a new technological means with which to: [1]

The use of nanotechnology in construction is strongly linked to sustainability. It is the declared aim of many nations to improve energy efficiency and reduce greenhouse gases. The first phase of the Kyoto Protocol ends in 2012 and a follow-on agreement will lay down further measures. CO2 emissions across the world must be halved by 2050 and this is only possible with resolute and above all immediate action. Energy efficient construction is therefore imperative,

particularly as construction is a major producer of CO2 emissions. [1]

Architects and planners are called upon to find innovative solutions for slowing climate change, to combine ambitious architecture with energy efficiency. The use of materials and surface properties that have now become possible through Nanotechnology offer architecture, interior architecture and related disciplines a means of achieving greater energy efficiency and sustainable construction through innovation. [1]

Nanomaterials is about making the maximum use of functions provided by Nanotechnology, and with its help to bring about innovation, then the use of Nanotechnology is of lasting value and entirely irrespective of arbitrary fashions. To comprehend the implications and potential for design, a basic knowledge of the different functional possibilities is essential. The following points have therefore been arranged according to the properties of the Nanomaterials and surfaces offer, such as air-purifying, self-cleaning and so on, rather than by the chemical or physical principles they are based on, such as Photocatalysis. [1]

Visionary scenarios, particularly those that drive the development of new products by manufacturers, typically have an outlook of 15 to 20 years. Given the longevity of building constructions and the liability period of the architects, this outlook is comparatively short in 15 years most architects will still be liable for buildings planned today As such the use of Nanosurfaces and Nanomaterials in construction requires openness towards innovation and a willingness to employ new and forward-looking technologies, not only from the architect but also the client. [1]

A design or construction project is always a matter of context, i.e. it makes a difference

whether an application is employed in a football stadium or a private villa. An understanding

of the context is also important in order to convey how products are implemented in the

practice of designing our environment. Without the context, a picture of a product, photographed in a warehouse, would have sufficed, or perhaps simply a description without illustrations, as "Nano" is invisible to the human eye anyway. By contrast, architecture, interior design and related disciplines are concerned with real and visible applications. [1]

• Tackle climate change.

• Help reduce greenhouse gas emissions in the foreseeable future.


21

2.3.1. Coatings (Finishing Materials):

Coatings are an area of significant research in nanotechnology and work is being carried out on concrete and glass as well as steel. Much of the work involves Chemical Vapor Deposition (CVD), Dip, Meniscus, Spray and Plasma Coating in order to produce a layer which is bound to the base material to produce a surface of the desired protective or functional properties. Research is being carried out through experiment and modeling of coatings and the one of the goals is the endowment of self healing capabilities through a process of “self-assembly”. [8]

Nanotechnology is being applied to paints and insulating properties, produced by the

addition of Nano-sized cells, pores and particles, giving very limited paths for thermal

conduction (R values are double those for insulating foam), are currently available. This type

of paint is used, at present, for corrosion protection under insulation since it is hydrophobic

and repels water from the metal pipe and can also protect metal from salt water attack. [8]

There are also potential uses in stone based materials. In these materials it is common to use resins for reinforcing purposes in order to avoid breakage problems, however, these resin treatments can affect the aesthetics and the adhesion to substrates. Nanoparticle based systems can provide

better adhesion and transparency than conventional techniques. [8]

In addition to the self-cleaning coatings mentioned above for glazing, the remarkable properties of TiO2 nanoparticles are being put to use as a coating material on roadways in tests around the world. The TiO2 coating captures and breaks down organic and inorganic air pollutants by a photocatalytic process (a coating of 7000 m2 of road in Milan gave a 60% reduction in nitrous oxides). This research opens up the intriguing possibility of putting roads to good environmental use. [8]

Coatings

Product: Self-cleaning:

Lotus-Effect

Self-cleaning:

Photocatalysis

Easy-to-clean

(ETC):

Antibacterial

Properties: Hydrophobic - water trickles off.

Hydrophilic surfaces.

Deposited dirt is broken down and lies loose on the surface.

hydrophobic, i.e. water-repellent and often also oleo phobic

Surface repellence without using the Lotus-Effect.

Bacteria are targeted and destroyed.

Specifications: Microscopically rough, not smooth.

Well suited for surfaces that are regularly exposed to sufficient quantities of water

A water film washes dirt away.

UV light and water are required.

Light transmissions for glazing and translucent membranes are improved.

Smooth surfaces with reduced surface attraction.

Surfaces have a lower force of surface attraction due to a decrease in their surface energy

The use of disinfectants can be reduced.

Silver nanoparticles reduce the amount of cleaning time necessary.

Usage: For better optimal use and low maintenance façades (self-cleaning).

Reduces the extent of dirt adhesion on surfaces.

Are most commonly found in interiors, but can also be employed outdoors for better weather protection.

Supports hygiene methods especially in health care environments.


22

2.3.1.1. Self-cleaning: Lotus-Effect: [1]

- Microscopically rough, not smooth.

- Hydrophobic - water trickles off.

This is one of the best-known means of designing surfaces with Nanomaterials. The name "Lotus-Effect" is evocative, conjuring up associations of beads of water droplets, and therefore the effect is often confused with "Easy-to-clean" surfaces or with Photocatalysis, which is also self-cleaning.

Self-cleaning surfaces were investigated back in the 1970s by the botanist Wilhelm Barthlott. He examined a self-cleaning effect that can be observed not only in oriental Lotus leaves (see Figure 2.11) but also in

the European Nasturtium, the American Cabbage or South African Myrtle Spurge.

They exhibit a microscopically rough water-repellent (hydrophobic) surface (see Figure 2.12), which is covered with tiny knobbles or spikes so that there is little contact surface for water to settle on. Due to this microstructure, surfaces that are already hydrophobic are even less wettable (see Figure 2.13). The effect of the rough surface is strengthened still further by a combination of wax (which is also hydrophobic) on the tips of the knobbles on the Lotus leaves and self-healing mechanisms, which results in a perfect, super-hydrophobic self-cleaning surface. Water forms tiny beads and rolls off the leaf, taking with it any deposited dirt (see Figure 2.14). If leaves should be damaged they heal on their own.

Artificial "lotus surfaces", created with the help of

nanotechnology, do not as yet have any self-healing capabilities, but they can offer an effective means of self-cleaning when properly applied. The Lotus-Effect is most well suited for surfaces that are regularly exposed to sufficient quantities of water, e.g. rainwater, and where this can run off. Small quantities of water often lead to water droplet "runways" forming or drying stains, which may leave a surface looking dirtier rather than cleaner without the presence of water, the use of such surfaces makes little sense.

Figure2.11: The Lotus plant with its natural self-

cleaning qualities lends its name to the "Lotus-

Effect".

Figure2.12: A microscopic view of a water droplet

resting on a super hydrophic and visibly knobbly

surface. The surface is covered with 5-10

micrometer-high knobbles, here enlarged, which

themselves are covered with a nanostructure and

have waxy tips.

Figure2.14: Water channels formed by water droplets running off

natural surfaces and a building Façade.

Figure2.13: The micro-structure of the surface of a

Façade coated with a nanotechnology-engineered

Lotus-Effect color coating emulates that of its

natural namesake.


23

- Here is an example for the use of the self-cleaning Lotus Effect applied on a building surface for a better optimal use and low maintenance façades:

1- Ara Pacis Museum, Rome, Italy: [1]

Architecture Richard Meier & Partners, NYC, USA.

Product Lotusan, self-cleaning paint (Lotus-Effect).

Manufacturer Sto.

Opened 2006.

After ten years of construction and political debate, the Ara Pacis Museum is now home to an archaeological highlight in Rome. The Ara Pacis Augustae, a sacrificial altar that was inaugurated by the Emperor Augustus himself, was given a new container that remedies the environmental as well aesthetic deficits of the previous pavilion from 1938 in which the monument was formerly kept. A tripartite building complex has been created on the banks of the River Tiber, whose urban form now fits in with the historic centre of Rome, and which connects antiquity with the modern.

The complex consists of an entrance gallery with an urban square in front, the main building with the exhibits, conference rooms and restaurant as well as further areas with space for temporary exhibitions, library and offices. The monument itself, the "Pax Augusta", is now contained within a transparent glazed part of the building and protected against damage from the environment. The remainder of the building is characterized by large blocks of travertine, typical for Rome, and surfaces clad in white, as is typical for Meier's architecture.

- Here a self-cleaning coating has been invisibly integrated into the white surfaces to ensure the durability of their color. In the heavily polluted city, it would not otherwise have stood much chance of remaining white for long.

Figure 2.15: Ara Pacis Museum exterior, showing

self cleaning coating.

Figure 2.16: The diagrams show clearly the

difference between conventional surfaces and

the Lotus-Effect.

Figure 2.17: Ara Pacis Museum exterior.


24

2.3.1.2. Self-cleaning: Photocatalysis: [1]

- Hydrophilic surfaces.

- Deposited dirt is broken down and lies loose on the surface.

- A water film washes dirt away.

- UV light and water are required.

- Reduces maintenance requirement.

Photocatalytic self-cleaning is probably the most widely used Nano-function in building construction, with Japan leading the field. There are numerous buildings of all sizes around the world that make use of this function. Its primary effect is that it greatly reduces the extent of dirt adhesion on surfaces. It is important to note that the term "self-cleaning" in this context is misleading and does not mean, as commonly assumed that a surface need not be cleaned at all. Fewer detergents are required, resulting in less environmental pollution and less wear and tear of materials. Likewise reduced cleaning cycles lead to savings in personnel costs and the fact that the dirt adheres less means that it is also easier to remove (see Figure 2.18 – 2.19).

Generally speaking, photocatalytic self-

cleaning is a low-maintenance and trouble-free

solution.

A further advantage is that light transmission for glazing and translucent membranes are improved as daylight is obscured less by surface dirt and grime. Energy costs for lighting can be reduced accordingly.

For the function to work, UV light, oxygen and

air humidity are required (see Figure 2.20). The level of UV light present in normal daylight is sufficient to activate the photocatalytic reaction. Organic dirt on the surface of a material is decomposed with the help of a catalyst - usually titanium dioxide (Ti02, and the particularly reactive derivative Anatase). The nanoscale dimension of Ti02 makes it a highly reactive catalyst, speeding up the decomposition process rapidly without being used up so that the effect is lasting.

Figure2.18: Oleo phobic surfaces are resistant against oils and fats.

Figure 2.19: Before and after: On conventional

tiles, water forms droplets that dry leaving behind

dirt deposits. On the hydrophilic surfaces of

photocatalytic tiles, water forms a film that runs off

taking any loose dirt deposits with it.

Figure 2.20: The diagrams show the bask process:

Organic dirt and grime is broicen down and

"decomposed". Until now UV light, such as present

in sunlight, is necessary to initiate photocatalysis.

When water impacts on the surface, it spreads to

form a film washing away the loose dirt. The result:

clean surfaces!


25

In addition to the catalyst, the UV component of light, with a wavelength of less than 390 nm is considered essential for the reaction to occur, and its intensity plays an important role. As such, photocatalytic self-cleaning surfaces are generally speaking more effective outdoors than indoors. The method is predestined, for example, for use on building Façades.

The hydrophilic properties of Ti02 were discovered much later. Due to its increased surface energy such surfaces are hydrophilic (water-attracting), which means that water runs off from any inclined surface in a film rather than in droplets (see Figure 2.21). In comparison to Lotus-Effect surfaces, this coating is transparent and can be applied to glass invisibly. Photocatalytic surface coatings are often applied to Façade panels made of glass or ceramics or to membranes.

In production, it is only economical for mass-produced glass as the coating is usually applied in the factory using chemical vapor deposition (CVD), a vacuum coating technique in which an ultra-thin coating is applied in vapor form. Such coatings cannot be retrofitted. However, this does not limit its application exclusively to large buildings; it can be equally appropriate for example for conservatories and winter gardens. In road building the transparent coating can also be used, for example for noise barriers. Tiles with baked - on durable coatings are available for use both indoors and outdoors. Likewise, concrete, another common building material for Façades, can also be equipped with a self-cleaning surface.

Photocatalytic glass can be combined with other typical functions such as solar-protection glass. The market for self-cleaning coatings is expanding most rapidly in Japan, where it has become common practice in many cases for new glazed Façades. The variety of photocatalytic applications already available on the market is quite varied and ranges from windows to vacuum cleaners to fridge-freezer deodorizing units. In addition to the self-cleaning properties, Photocatalysis can also be used to achieve air-purifying, water-purifying as well as antimicrobial properties.

Figure 2.21: TiO2 and PVC coated white membranes in weathering tests. The difference is readily apparent: after five

months the former is still white, the latter grey and unsightly.


26

- Here is an example for the use of the self-cleaning Photocatalysis applied on a building surface for a better optimal use and low maintenance façades:

1- Muhammad Ali Center MAC, Louisville, Kentucky, USA: [1]

Architecture Beyer Blinder Belle Architects & Planners LLP, in cooperation with Lee H.

Skolnick Architecture + Design Partnership, New York, NY, USA.

Product Hydrotect, photocatalytic self-cleaning ceramic tiles.

Manufacturer Agrob Buchtal architectural ceramics, Deutsche Steinzeug America.

Opened 2005.

In the home town of the boxing legend Muhammad Ali, "The Greatest", his life's dream has become built reality: the MAC is an international cultural centre that promotes individual talent and respectful understanding of one another. It is therefore more than a Muhammad Ali Museum, and caters for seminars, lectures, films, exhibitions, symposia and so on.

Prominently positioned on the banks of the River Ohio, the building has a striking appearance, in particular due to its façade. Ceramic tiles with different color glazing are arranged on a 30*60 cm grid according to a particular pattern. From a distance it appears as an oversized mosaic depicting typical boxer stances and a likeness to Muhammad Ali.

From close-up the figurative depiction gives way to an abstract pattern. To maintain a consistently good appearance and to keep down the cost of cleaning, the tiles are equipped with a photocatalytic self-cleaning surface coating.

The coating is baked onto the glaze of the tiles and is therefore indefinitely durable. In addition the surface is also air-purifying, breaking down pollution and exhaust gases from vehicles and industry in the surrounding atmosphere. Investigations have shown that l.000 m2 of photocatalytic façade has the equivalent effect of 70 medium-sized deciduous trees.

Figure 2.22: Muhammad Ali Center MAC exterior.

Figure 2.23: Ceramic tiles with self-cleaning Photocatalytic used in Muhammad Ali Center MAC exterior façade.


27

2- Narita International Airport of Tokyo, Terminal 1, Chiba, Japan: [1]

Architecture Nikken Sekkei Ltd., Japan.

Product Ever Fine Coat / Ti02 photocatalytic self-cleaning membrane.

Manufacturer Taiyo Kogyo Corporation.

Opened 2006.

In 2006, the Narita International Airport in Tokyo underwent comprehensive renovation. In the process large sections were covered with textile roofing. Membranes offer protection against the weather and therefore improve comfort for passengers.

As the membranes are equipped with a photocatalytic self-cleaning coating, the cost of cleaning and maintenance is kept to a minimum.

In central areas of Tokyo, the use of self-cleaning

awnings has been common practice for several years and they have proven to remain much cleaner than their conventional counterparts.

Although conventional surface coatings, glass, PTFE or ETFE materials are also self-cleaning, they are not able to stop dirt deposits from accumulating.

Figure 2.24: Narita International Airport exterior.

Figure 2.25: Narita International Airport exterior.


28

2.3.1.3. Easy-to-clean (ETC): [1]

- Smooth surfaces with reduced surface attraction.

- Surface repellence without using the Lotus-Effect.

Easy-to-clean (ETC) surfaces are water-

repellent and accordingly are often confused with other self-cleaning functions such as the Lotus-Effect. However, unlike the latter, easy-to-clean surfaces are smooth

rather than rough. These surfaces have a lower force of surface attraction due to a decrease in their surface energy, resulting in reduced surface adhesion. This causes water to be repelled, forming droplets and running off. Easy-to-

clean surfaces are therefore hydrophobic (see Figure 2.26), i.e. water-repellent and often also oleo phobic, i.e. oil-repellent, making them well suited for use in bathrooms.

The easy-to-clean function of surfaces is also often confused with other photocatalytic self-cleaning functions. The primary difference here is that easy-to-clean surface coatings do not require UV light to function and their hydrophobic surface properties - as opposed to hydrophilic - cause water to run off in droplets rather than forming a thin film of water. Similarly, ETC surfaces should not be confused with Teflon coatings: Teflon (PTFE) exhibits multi-directional non-stick properties, and its graphite fill material gives PTFE its characteristic dark coloring, which is anything but transparent.

Water droplets are not always beneficial and can have disadvantageous effects: the spherical form of water droplets has the smallest surface area to volume ratio of all volumes. The drying time is correspondingly longer and this should be taken into consideration for particular areas of application. A disadvantage is that droplets dry individually, leaving behind dirt residues -although these are easy to remove.

One should select products that have proven their resilience in reliable testing procedures. Likewise, where small print in product details recommends gentle cleaning and the avoidance of abrasive cleaning agents, this should not be ignored, in order to ensure the longevity of the product (see Figure 2.27).

Super hydrophobic materials and coatings are therefore most beneficial where dirt accumulation needs to be kept to a minimum and water repellence ensured. ETC surfaces are most commonly found in interiors, but can also be employed outdoors for better weather protection (see Figure 2.28).

Figure 2.26: "Roll-out marble"- Impact-resistant,

fire-retardant, vapor permeable and yet water-

repellent and easy-to-clean. The product consists

of four layers:

1- a flexible polymer matting as backing

2- colored ceramic materials is applied

3- optional printing

4- ceramied top coat

Figure 2.28: Ultra-clean white surfaces of poolside

armchairs, achieved using water-repellent surface

coatings.

Figure 2.27: A comparison of ceramic surfaces –

left without ETC coating, right with ETC coating.

Figure 2.29: The angle of contact determines the

hydrophobic degree of a surface. The contact angle

describes the degree of wetting, and is a function of

the relative surface tensions of the solid, water and

air.


29

- Here is an example for the use of the Easy To Clean (ETC) applied on a building surface for a better optimal use and low maintenance façades:

1- Kaldewei Kompetenz-Center (KKC), Ahlen, Germany: [1]

Architecture Bolles + Wilson, Miinster, Germany.

Product Kaldewei steel-enamel with self-cleaning "Perl-Effect" easy-to-clean surface.

Manufacturer Kaldewei.

Opened 2005.

Kaldewei is unique among bath manufacturers in that it has its own in-house enamel development and production facilities.

By wrapping its building in a veil-like facade of colored steel-enamel panel elements, behind which the existing melting facilities can be seen, the company expresses its brand through architecture.

The enameled facade panels are colored in the company's typical color palette and are partially equipped with an easy-to-clean coating.

This coating is otherwise used in the manufacture of bathtubs to further improve the ease with which one can clean the already low-maintenance material.

Figure 2.32: Kaldewei Kompetenz-Center (KKC)

exterior. Figure 2.31: Kaldewei Kompetenz-Center (KKC) interior.

Figure 2.30: The enameled facade panels of

Kaldewei Kompetenz-Center (KKC).


30

2.3.1.4. Antibacterial: [1]

- Bacteria are targeted and destroyed.

- The use of disinfectants can be reduced.

- Supports hygiene methods especially in health care environments.

Photocatalytic surfaces also have an

antibacterial side effect due to their ability to break

down organic substances in dirt. With the help of silver nanoparticles it is possible to manufacture surfaces specifically designed to be antibacterial or germicidal. Whether in the form of ultra-thin and invisible coatings or materials to which the particles have been added, these have an effect stronger than antibiotics. Various products are already commercially available and the product palette ranges from floor coverings to panel products and paints to textiles with an innovative finish that renders them germ-free.

There are areas where bacteria can indeed be damaging. In hospitals, for example, harmful bacteria abound on the one hand and weaken patients on the other. The deployment of disinfectants has now changed, becoming more directed, as opposed to the "blanket approach" previously used. Like hospitals, doctor's practices also fight an ongoing battle against germs, with a multi-pronged approach involving disinfectants, antibiotics and building up resistance.

Medicinal equipment, when coated accordingly, remains germ-free (see Figure 2.33). For example, hearing aids that reduce inflammations have proved most successful. In interior architecture all surfaces are suitable candidates for antibacterial surface coatings, whether enclosing surfaces such as floors, walls and ceilings or furnishing such as textiles, sanitary installations, shelves and worktops, and in particular knobs, buttons and switches that are in constant use by patients and staff (see Figure 2.34).

The antibacterial effect of silver results from the ongoing slow diffusion of silver ions. The very high surface area to volume ratio of the nanoparticles means that the ions can be emitted more easily and therefore kill bacteria more effectively. The antibacterial effect itself is also permanent - it does not wear off after a period of time.

Silver nanoparticles not only reduce the need for chemical disinfectants but also reduce the amount of cleaning time necessary. As the use of disinfectants in health care cannot yet be avoided, it is important that coatings and materials are proven to be able to withstand standard disinfectants. Antibacterial surfaces based on silver nanoparticles represent an effective and unobtrusive bacterial killer, which when employed sensibly can offer significant benefits.

Figure 2.33: Sanitary, care and medical facilities are

areas particularly susceptible to germ transmission.

This can be counteracted through the use of

antibacterial surface coatings that react against

many of the more important pathogens. The

antibacterial agent is a constituent part of the

material itself.

Figure 2.34: Curtains with antibacterial properties.

- Contact surfaces such as light switches,

door grips and handles are typical germ

accumulators. An antibacterial material,

such as that used for this light switch, can

prevent germs spreading.


31

- Here is an example for the use of the Antibacterial applied on a building surface for a better optimal use and low maintenance façades:

1- Housing estate, Duisburg, Germany: [1]

Architecture Joachim Osterland, Essen, Germany.

Product Bioni Perform, antibacterial facade paint.

Manufacturer Bioni CS.

Opened 2004.

The mould on the facades of this housing estate in Duisburg proved hard to eradicate. In the past a combination of insulation and fungicidal silicon resin-based paint was used to resolve the problem, however the remedy lasted only two years. Microbe infestation became visible again and mould and mildew formation followed soon after, necessitating a second renovation of the elevations.

This time a solution developed by the renowned Fraunhofer Institute for Chemical Technology in collaboration with a paint manufacturer was chosen. Silver nanoparticles of on average 10-15 nm in size lend the paint antimicrobial properties that remove the basis for mould and mildew. The particles are chemically stable and firmly anchored in the paint. The antimicrobial agent therefore cannot be washed out and the antibacterial function remains intact for many years. Three years later, no mould infestation is to be seen. The use of nanotechnology in this case offers an environmentally friendly and effective solution without the need for strong chemicals, and prevents further damage to the elevations.

The same facade coating has been used for the very large and world-famous "The Palm" complex in Dubai (40,000 m2 of roof surface). Antibacterial wall paints have also been used in the interiors of the Al Wasl Hospital, also in Dubai. In hospitals in particular, where hygiene is a central aspect, biocide-free antibacterial paints offer major advantages.

Figure 2.35: The mould on the facades of Housing

estate.

Figure 2.36: The Antimicrobial paint was used on

the façades of housing estate.


32

2.3.2. Insulation (Energy Saving Materials):

Since the dawn of time, man has recognized the need for insulation to keep warm. Ancient Greeks and Romans used asbestos and cork to reduce heat loss during the winter and to keep cool during the summer. Today we are turning to nanotechnology to contribute more efficient ways to keep warm and conserve energy. [9]

Insulating materials are used to keep the temperature constant in an enclosed space to protect the environment through the reduction of CO2, NO2 and greenhouse gases. Substantial quantities of energy are wasted daily in both homes and industry because of poor insulation. Advances in insulation will help reduce both energy demand and cost. [9]

The basic requirement for thermal insulation is to provide a significant resistance path

to the flow of heat through the insulation material. Insulating materials can be adapted to any size, shape or surface. [9]

Current materials used for insulation include fiberglass (see Figure 2.37), rock wool, and slag wool. While these materials are renewable, nanotechnology can offer better alternatives. One form of insulation is to fill in airspaces in materials by using air or liquid. Most insulating materials are therefore porous. Nanotechnology has contributed to this area in the form of aerogels. [9]

Figure 2.37: Fiberglass insulation (OwensCorning).

Insulations

Product: Thermal Insulation:

Vacuum insulation

panels (VIPs)

Thermal Insulation:

Aerogel

Temperature

regulation: Phase

change material

(PCMs)

Properties: Maximum thermal insulation.

Minimal insulation thickness.

High-performance thermal insulation.

Effective sound insulation.

PCMs are invariably made from paraffin and salt hydrates.

Specifications: An enveloping skin made of plastic foil or of stainless steel. The fill material takes the form of foam, powder or glass fibers.

Light and airy nanofoam.

Aerogel contributes towards energy efficiency.

Reduced heating and cooling demand.

Passive temperature regulation.

Usage: Used both for new building constructions as well as in conversion and renovation work and can be applied to walls as well as floors.

Nanogel-filled glass panels are suitable for use in Façades but also for interiors.

Conserving energy by reducing the energy demand for heating and cooling.


33

2.3.2.1. Thermal insulation: Vacuum insulation panels (VIPs): [1]

- Maximum thermal insulation,

- Minimal insulation thickness.

Vacuum insulation panels (VIPs) are ideally

suited for providing very good thermal insulation

with a much thinner insulation thickness than usual (see Figure 2.38). In comparison to conventional insulation materials such as polystyrene, the thermal conductivity is up to ten times lower. This results either in much higher levels of thermal resistance at the same insulation thickness or means that thinner insulation layers are required to achieve the same level of insulation. In other words, maximum thermal resistance can be achieved with minimum insulation thickness. Vacuum insulation panels can be used both for new building constructions as well as in conversion and renovation work and can be applied to walls as well as floors.

The panels are constructed as follows: an enveloping skin made of plastic foil (often coated with aluminum) or of stainless steel encloses the fill material in a vacuum. The fill material takes the form of foam, powder or glass fibers and is always porous, resists pressure and can be evacuated.

There are several aspects that should be taken

into account in planning practice. In particular:

1- Wherever possible standard dimensions should be used. 2- For the panels to function correctly, it is imperative that the vacuum-enclosing skin is

not pierced. One should employ a combination of panel sizes or use panels that are factory-made with predefined openings.

3- The panels must be handled with care; both on site and during transport, to avoid damaging the panel's relatively sensitive skin (see Figure 2.39). A loose skin indicates that the VIP has been damaged.

The efficiency of the insulating effect, regardless of the thermal conductivity coefficient

stated, is not only a factor of its installation but also the size of the panels. Large format

panels are more advantageous.

VIPs are more expensive than conventional insulation materials and today are not necessarily conceived as a general replacement for conventional insulation. Vacuum insulation

panels offer great potential in the general context of improving energy efficiency through

better insulation and accordingly contribute to reducing the amount of CO2 emissions.

The lifetime of modern panels is generally estimated at between 30 and 50 years, with

some products exceeding 50 years. A number of factors contribute to this, including the

integrity of the skin, the degree of vacuum within, the seal and last but not least the correct

installation of the product.

Figure 2.38: Vacuum insulation panels with a

protective encasement.

- Different sized vacuum Insulation panels in

storage.

Figure 2.39: VIP insulation must be made to

measure and fitted precisely on site.


34

1- Seitzstrasse mixed-use building, Munich, Germany:

Architecture Pool architekten, Martin Pool, Munich, Germany.

Product Vacuum insulation panel (VIP).

Manufacturer Va-Q-tec, Wiirzburg, Germany.

Opened 2004.

The seven-storey mixed-use residential and commercial building in Munich is the first building of a substantial size to be fully clad with vacuum insulation panels (VIPs). Despite adverse factors, the freestanding building fulfils ultra-low energy standards. [1]

The compact rectangular form of the white building is punctured by large windows that wrap around its corners. At between eight and ten times greater efficiency than conventional insulation materials, the ultra-slim VIPs are extremely good insulators. Their potential lies not only in reducing energy consumption but also in maximizing the available area as a result of thinner wall constructions. The use of VIPs resulted in a floor area gain of 10% of the overall floor area. [1]

VIPs were also used in the roof terrace and window constructions. This inner-city building illustrates how the use of VIPs leads to energy savings as well as increased economic returns. [1]

Thermographic studies (see Figure 2.41) taken last year show that none of the panels have been damaged, (ZAE 2008). [6]

Figure 2.41: Thermography of the building. Figure 2.42: Building in the vacuum insulation

between the purenit battens.

Figure 2.40: Seitzstrasse mixed-use building.


35

2.3.2.2. Thermal insulation: Aerogel: [1]

- High-performance thermal insulation.

- Light and airy nanofoam.

In comparison to the relatively well-known self-cleaning properties of Nano-based surfaces, nanotechnology-infused thermal insulation represents a new development. A product known as Nanogel, a

form of aerogel (see Figure 2.43), not only provides

high performance thermal insulation but also

effective sound insulation.

Aerogel currently holds the record as the lightest known solid material and was developed back in 1931. The current variant used in construction has been produced by the Canadian Cabot Corporation in Frankfurt am Main for several years. The gel is a globular granulates and appears milky, translucent and somewhat cloudy. When held in the hand, the pure material has an extraordinary, fascinating and otherworldly feel to it that eludes comparison with most other haptic experiences.

In reality aerogel is relatively banal: it is simply ultra-light aerated foam that consists almost 100% of nothing other than air (the exact figure varies between95% and 99.9%). The remaining foam material is a glass like material, silicon dioxide, also known as silica.

The nanodimension is of vital importance for the pore interstices of the foam: the air molecules trapped within the minute nanopores - each with a mean size of just 20 nm - are unable to move, lending the aerogel its excellent thermal insulation properties. A side from reducing heat loss, in cool regions the "coldwall" effect is also less pronounced, whilst in hot climates heat transfer from outside is reduced.

Because it is translucent, aerogel exhibits good light transmission, spreading light evenly and pleasantly. UV light does not cause coloration of the material. Due to the hydrophobic property of the material, moisture and mould are not an issue.

Aerogel also acts as a sound insulator according to the same basic principle. The air molecules immovably trapped in the nanopores of the aerogel stop sound waves from passing through the material. As such Nanogel-filled glass panels (see Figure 2.45) are suitable not only for use in Façades but also for interiors, for instance as enclosures around conference areas in offices.

Figure2.43: Aerogels in combination with glass

Opaque Nanogel pearls.

- Translucent Nanogel granulates.

- Heaps of aerogel.

Figure 2.44: A dose-up of aerogel granulate.

Glazing elements filled with aerogel.

Figure2.45: Glass sample with black edging and

aerogel-filled glazing cavity.


36

1- County Zoo, Milwaukee, WI. USA: [1]

Architecture Zimmerman Design Group, USA.

Product Kalwall+ Nanogel glazing.

Manufacturer Kalwall Corporation.

Opened 2005.

Daylight is important not only for people. The Florence Mila Borchert Big Cat Country building, constructed mostly of stone and concrete, was beginning to show its age. Better natural lighting was needed to improve conditions for the big cats.

A key problem in this respect was the fulfillment of thermal performance and energy efficiency legislation. This was solved through the installation of aerogel-filled glass panels, which provide glare-free natural daylight whilst ensuring greater energy efficiency the lions should benefit measurably - daylight is supposed to have a positive effect on the reproductive cycle of the animals.

Figure 2.46: Country Zoo interior showing Nanogel

glazing used in roof.

Figure 2.47: Nanogel glazing material used in roof.


37

2.3.2.3. Temperature regulation: Phase change material (PCMs): [1]

- Passive temperature regulation.

- Reduced heating and cooling demand.

Regulating the temperature of buildings

consumes vast quantities of energy for both heating

and cooling, in the process producing CO2 emissions. With the help of nanotechnology, the energy consumption can be significantly reduced (Sustainable Energy). Latent heat storage, also known as phase change material (PCM), can be used as an effective means of regulating indoor room temperatures.

The use of phase change materials is not new. In ancient Baghdad, rooms were kept cool with the help of a natural PCM: ice. Research into PCMs has been undertaken for many years. In the context of building and construction, the main application area is for conserving energy.

PCMs are invariably made from paraffin and salt hydrates. Minute paraffin globules with a diameter of between 2 and 20 nm are enclosed in a sealed plastic sheathing. These can be integrated into typical building materials, whereby around 3 million such capsules fit in a single square centimeter (see Figure 2.48).

The predefined, so-called switching temperature, in which the phase change from one physical state to another occurs in latent heat storing materials designed for construction, is defined as 25°C, as above this temperature the indoor air temperature is generally regarded as being unpleasantly warm. Depending upon the PCM used, to regulate a 5°C increase in temperature only 1 mm of phase change material is required in comparison to 10-40 mm of concrete. The PCM has a far greater thermal capacity: a concrete wall warms up much more quickly whilst the temperature of a PCM remains unchanged.

In the meantime, PCMs have become available in the form of additives that can be integrated into conventional building materials such as plasters, plasterboards or aerated concrete blocks with specific retention properties (see Figure 2.49).

In addition to conserving energy by reducing the energy demand for heating and cooling, PCMs are also recyclable and biologically degradable. As with other innovative insulation materials, there is a large market for the use of PCMs in the construction industry, as they improve indoor climates, reducing costs and in some cases even obviating the need for air conditioning. With regard to the need to reduce CO2 emissions, PCMs offer potential chances to achieve that.

Figure 2.48: Close-up of a phase change material

embedded in glazing.

- Crystallization of a salt phase change

material.

- Wax droplets with an acrylic glass

sheathing that is practically Indestructible,

even by sawing or drilling.

- An image of an opened microcapsule

embedded in a concrete carrier matrix,

taken using scanning electron microscopy.

- An image of minute paraffin-filled

capsules in their solid state, taken using

light microscopy. They exhibit an

exceptionally high thermal capacity and

during a phase change turn to liquid.

Figure 2.49: Layer composition of a decorative PCM

gypsum plaster applied to a masonry substrate.

- Although only 15 mm thick, this

plasterboard panel contains 3 kg of micro-

encapsulated latent heat storage material

per square meter.


38

1- "Sur Falveng" housing for elderly people, Domat/Ems, Switzerland: [1]

Architecture Dietrich Schwarz, GlassXAG, Zurich, Switzerland.

Product Latent heat storing glass, phase change material (PCM), GLASSXcrystal.

Manufacturer GlassX.

Area 148m2 GlassXcrystal glazing.

An experienced architect, who is also a scientist, developed a latent heat storing glass, which was followed soon after by the founding of a start-up company under the name GlassX AG.

Among the projects realized using this glass is a building with 20 disabled-access sheltered flats in the Swiss Alps. All flats have large expanses of south-facing glazing and, depending on the season, the flats are heated actively or from passive solar gain.

The central of three cavities of an 8 cm thick composite glass element contains a salt hydrate fill

material that functions as a latent heat store for solar heat and protects the rooms from overheating. The latent heat store has a thermal absorption capacity equivalent to a 15 cm thick concrete wall. The glass panel is transparent when the fill material has melted and milky-white when frozen.

The material's change of state is therefore immediately reflected in the building's appearance - function and aesthetics are inseparably connected. The buffer function of the latent heat store enables the indoor temperature to be regulated mostly passively, resulting in significant energy savings for heating and cooling.

Figure 2.51: "Sur Falveng" housing for elderly people exterior façade.

Figure 2.50: "Sur Falveng" housing for elderly

people interior.


39

2.3.3. Air-purifying (Environmental Material): [1]

- Pollutants and odors are broken down into their constituent parts.

- Does not replace ventilation, but improves air quality.

Though not able to completely purify air, the use of Nanomaterials is possible to

improve the quality of air. It enables unpleasant odors and pollutants to be eradicated (Sustainable Environment). The air-purifying properties of Nanomaterials are beneficial in both cases and play an important role both for indoor as well as increasingly for outdoor environments.

2.3.3.1. Indoors:

The indoor air quality is particularly important in industrialized nations where people spend a large amount of time indoors and unpleasant smells or even pollutants are commonly associated problems. Although our sense of smell greatly influences our general feeling of well-being, it is all too often neglected.

We usually deal with this problem by more or less eliminating any unpleasant smells indoors, either by airing the room, by masking it with another perfume or with the help of restorative materials, though these have a limited capacity. Nanotechnology, on the other hand, makes it possible to chemically decompose odors into their harmless constituent parts. Here the molecules are cracked, giving off steam and carbon dioxide (see Figure 2.52 – 2.53).

This approach can also be used to counter act the sick building syndrome (SBS). To function adequately, the air-purifying surface area must be sufficient with regard to the volume of the room. Only surfaces that are exposed to the air, i.e. those not concealed by furniture, are relevant. For processes based on oxidative catalysis, normal air circulation is sufficient, however photocatalytic processes, which can also be used for air-purifying purposes, require daylight (see Figure 2.53).

Figure2.52: Air-purifying curtain materials can

simultaneously be equipped with antibacterial

properties. Various products are already available

on the market, with or without antibacterial

combination.

Figure 2.53: Air-purifying curtains across the width of this dance and work-out room help maintain a better indoor air quality.

- Air-purifying interior plaster.


40

Air purification technology is increasingly being used for textiles and paints (see Figure 2.54). It should be noted that although it is possible to improve the quality of air, this does not necessarily make it "good". Other factors such as oxygen content and relative humidity also contribute to the air quality and should not be neglected when using air purifying products. It would be wrong to assume that an air-purifying carpet means one no longer needs to open the window - it cannot replace regular ventilation. Insufficient ventilation leads to an inevitable build-up of relative humidity and eventually results in mould formation and further associated problems.

2.3.3.2. Outdoors:

Environmental pollution and the quality of air outdoors has long been a topic of public discussion in Europe, particularly as public education and awareness of ecological aspects and sustainable development increases. The air-purifying capacity of photocatalytic concrete for example provides a possible means of combating existing pollutants. Recently, building Façades, road surfaces and the like, equipped with appropriate coatings, are being implemented in test installations to counteract the effect of industrial and vehicle exhausts. It transpires that photocatalytic self-cleaning concrete for example also has an additional air-purifying effect. Applications are air-purifying paving stones (see Figure 2.55), road surfaces and paints. At present these materials are still expensive, but a start has

been made.

The efficiency of photocatalytic air-purifying surfaces was possible to eradicate between 20% and 80% of airborne pollutants. Pedestrians walking in the vicinity of treated walls breathed in fewer airborne pollutants.

As with indoor air environments, outdoor air purification applications are only a supporting measure for tackling symptoms and are an adequate means of reducing existing pollution (see Figure 2.56). They do not eradicate the cause of pollution but can be used to reduce smog and improve the outdoor air quality. The question is whether a noticeable difference to the quality of air can be made with the use of air-purifying surfaces, and how significant this effect actually is.

Figure2.54: Air-purifying materials such as

plasterboard or acoustic panels.

Figure 2.55: Photocatalytic pavement surfacing.

Figure 2.56: Concrete paving panels with

photocatalytic properties used as a design element

in a car park.


41

1- Jubilee Church, La Chiesa del Dio Padre Misericordioso, Rome, Italy: [1]

Architecture Richard Meier & Partners, NewYork, NY, USA.

Product TX MilIenium, TX Active, photocatalytic cement.

Manufacturer ltaIcementi.

Opened 2003.

Three giant sails reaching up to 36m into the sky give this church and community centre its unmistakable appearance.

Made of prefabricated high-density concrete, their white color is achieved by adding Carrara marble and titanium dioxide to the mixture.

The photocatalytic self-cleaning additive enables the architect to achieve his trademark white coloring in an urban environment that is heavily polluted by car exhaust gases.

The building not only remains clean, the large surface area of the sails also helps combat pollution by reducing the amount of volatile organic compounds (VQCs) and nitrogen oxide in the air considerably.

Figure 2.57: Jubilee Church Exterior showing self-

cleaning concret.

Figure 2.58: Jubilee Church Exterior.


42

2.3.4. Solar protection (Environmental Material): [1]

- NO blinds necessary.

- Glass darkens automatically or is switchable without the need for a constant electric current

(memory effect).

Solar protection against heat gain from solar radiation is offered by two kinds of self-

darkening glass. Electrochromatic switchable glazing was previously available on the market, but has since largely disappeared due to two main disadvantages: a constant electric current was necessary to maintain a darkened state and larger glass surfaces often exhibited optical irregularities.

The advent of nanotechnology has provided a new means of integrating

Electrochromatic glass in buildings. The primary difference to the earlier product is that a

constant electric current is no longer necessary. A single switch is all that is required to change the degree of light transmission from one state to another, i.e. one switch to change from transparent to darkened, and a second switch to change back. Different levels of light transmission with various darkening effects are also possible, either as a smooth gradient or clearly differentiated. The electrical energy required to color the ultra-thin nanocoating is minimal. The switching process itself takes a few minutes, which can appear quite slow. The range of panel sizes currently available is relatively limited as the products have only recently come onto the market - the maximum size at present is 120 X 200 cm (see Figure 2.59). Further panel sizes and improved switching speeds can be expected in the future.

The integration of Electrochromatic glazing in a building's technical services affords greater control, although it is still advisable to allow users the ability to control glass panels individually. It is generally possible to combine the Electrochromatic function with other glazing properties such as laminated safety glass or thermal or noise insulating glazing. In future colored glazing should also be available, expanding the design possibilities greatly.

Photochromatic glass is another solution for darkening glass panels. Here the sunlight

itself causes the glass to darken automatically without any switching.

In both cases blinds or curtains may no longer be necessary. Glare-free light and shading is particularly important for office interiors with computer workstations. Both variants also provide partial shading rather than complete closure so that a degree of visual contact to the world outside always remains. Nanotechnology has made it possible to provide an energy-efficient means of solar protection that can also be combined with other glass functions.

Figure 2.59: Electrochromatic glass with an ultra-thin nanocoating needs only be switched once to change state, gradually changing

to a darkened yet transparent state. At present the maximum dimension of glazing panels is limited.


43

2.3.5. Fire-proof (Environmental Material): [1]

- Highly efficient fire protection.

- Light and transparent.

In the Nano-scene, a relatively small company from Switzerland, Interver Special Glass Ltd., has made headlines with its fire safety glass. A thickness of only 3 mm of a functional fill material (see Figure 2.60) between glass panels is sufficient to provide more than 120 minutes of fire resistance against constant exposure to flames of a temperature of over 1000°C. The product was developed in cooperation with the German chemical concern Degussa, which has produced particles of "between 4 and 20 millimicrometres" under the name Aerosil for over half a century and is a major producer in the field. The raw material Aerosil, a pyrogenic silicic acid, is produced by Degussa and used for a number of purposes including in the paint industry.

The main advantages are the comparatively

light weight of the glass, the slender construction and

accompanying optical appearance as well as the long

duration of fire-resistance. In the event of fire, the fire-resistant layer expands in the form of foam preventing the fire from spreading and keeping escape routes accessible for users and firemen alike. The additional layer does not exhibit any clouding, streaking or fractures and is practically invisible. An additional side effect is improved noise insulation.

In the event of a fire the nanosilicate forms an opaque protective layer against the fire, which also protects against heat radiation. In terms of design, the first ever curved fire safety glazing is of interest. In addition "flush glazing" is also possible, with individual panes directly abutting without the need for vertical mullions.

Flame-resistant lightweight building boards, sandwich constructions made of straw and hemp (see Figure 2.61), are a further interesting application. Originally developed for rapid construction in developing countries with special climatic needs, these panels can also be used for interiors and exhibition stands. By coating the product in a transparent covering of glass-like particles, it is possible to render it weatherproof and flame-resistant.

Figure 2.60: The gel fills material in the glazing cavity (here faulty but clearly visible) foams when exposed to fire for an extended

period.

Figure 2.61: A robust sandwich panel made of straw

and hemp with a glassy coating that serves as a

bonding agent and is also fire-resistant. When

exposed to fire the product smoulders and

extinguishes.


44

1- Deutsche Post headquarters, Bonn, Germany: [1]

Architecture Murphy/Jahn, Chicago, IL, USA.

Product SGG Contraflam fire safety glass.

Manufacturer Vetrotech SaintGobain.

Opened 2005.

The landmark 160 m high office tower in Bonn, the former capital city of Germany on the River Rhine, accommodates more than 2000 members of staff.

The oval tower's facade is clad in high-tech transparent glazing and transparent materials are also used throughout its interiors: glazed partitions, glazed staircases and glazed connecting bridges are central elements of the interior design concept.

A fire safety glass with a particularly slender profile was selected for the project. Space, form, construction and materials are carefully coordinated, resulting in a harmonious overall concept.

Figure 2.62: Deutsche Post headquarters Exterior.

Figure 2.64: Deutsche Post headquarters fire safety

glass. Figure 2.63: Deutsche Post headquarters interior.


45

2.3.6. Scratchproof and abrasion-resistant: [1]

- Improvement of scratch and abrasion resistance.

- Transparent coating.

- Creating a basis for durability.

Nanotechnology makes it possible to improve scratch resistance whilst maintaining transparency. Scratch resistance is a desirable property for many materials and coatings can be applied to materials of different kinds such as wood, metal and ceramics. There is no ideal coating, rather two basic principles apply: self-healing layers, which are less susceptible to scratching, or glass-like hard scratch-resistant layers.

Materials are generally subject to wear and tear by abrasion, e.g. from being walked on, from scrubbing and cleaning or similar. The science of how materials behave under friction and wear is known as tribology. Nanotechnology has made so-called tribological coatings possible, which offer abrasion-resistance or low friction and are therefore resistant against wear and tear and also corrosion.

For architectural applications, recently developed scratch-resistant stainless steel coatings are of particular interest and are available in transparent or colored form. Scratchproof lacquers are a standard feature of certain car models. The protective layer preserves the gloss of a vehicle's paint, avoiding damage from quartz dust hitting a car while driving or scratching in the car wash (see Figure 2.65).

In the architectural context, scratchproof paints and varnishes are desirable, for instance to protect the varnished surfaces of parquet flooring or the surfaces of other gloss lacquered surfaces. Consumers who associate patina with negative connotations such as a "lack of care" and "old and worn" will value a durable gloss that maintains its original appearance. Not everyone shares the love that many architects have for authentic patina.

Figure 2.65: Scratchproof varnishes are not able to withstand major damage, for instance scratches from a key, but they can

protect a car from scratching resulting from a car wash or from dirt and dust in transit. Layers of a protective varnish.

- Abrasion tests indicate a surface's resilience against abrasion and wear and tear.

Scratch-resistant surfaces in combination with UV protection and easy-to-clean

properties seem to be a particularly attractive combination for many users, in order to

reduce traces of use. Likewise cleanly designed surfaces maintain their appearance better

through the use of scratchproof and abrasion-resistant surfaces.


46

2.4. Nanomaterials Costs:

The enormous potential for widespread Nanomaterials applications to occur inherently depends on the availability of large quantities of Nanomaterials at reasonable costs. In the current emerging state of the field, not all Nanomaterials forms found in the laboratory are widely available, fewer still as commercialized products. [2]

Costs for Nanomaterials products are also high.

Costs are invariably a driving factor, one often cited

as an inhibiting factor in the development of

applications involving Nanomaterials and not without

good reason. In the early days of Nanomaterials

exploration, a gram of nanotubes could cost several

thousand dollars; even recently, 500 or so dollars per

gram was a common price. [2]

In the current context, many groups that commercially produce Nanomaterials (such as various kinds of nanoparticles or nanotubes) are just now transitioning from their roles as suppliers to the research sector to that of becoming producers of commodity products. This transition, in turn, is being driven by the development of more and more real applications that demand larger quantities, or by real product prospects just on the horizon (see Figure 2.66). The actual number of producers, however, is still relatively few in comparison to the multitude of businesses that produce conventional materials, and outputs remain relatively small. [2]

2.4.1. Types:

1- Nanoparticles for applications are already commercially available in a wide range of

forms that can support a host of applications. Fundamental types include basic elements, compounds, and oxides. Various alloys, carbides, sulfides, and other forms can also be obtained. Materials such as silver (Ag), gold (Au), aluminum (Al), and iron (Fe) are commonly available, as are many fundamental forms. A wide array of compounds (such as tungsten carbide, TiC) and oxides (such as titanium dioxide, TiO2) are also available.[2]

2- Titanium dioxide (TiO2), widely used in its anatase form for photocatalytic

applications (self-cleaning, antimicrobial), typically ranges from 5 to 20 nm, whereas in another of its forms (rutile) diameters are often larger (40–50 nm). [2]

3- Nanoparticles can also come in varying levels of treatments. Various nanoparticles can be obtained that, for example, already have hydrophobic or hydrophilic properties useful in a wide range of applications. [2]

4- Carbon nanotubes for applications are available in a wide variety of single-walled

(SWNT) and multiwalled (MWNT) forms, including different lengths, diameters, and

purities. A primary quality and cost issue is purity. Depending on the synthesis process used, purified forms are characterized by descriptions such as “95 wt%” or “60 wt%,” which simply refers to the actual percentage by weight of nanotube content within a unit weight of a gram of nanotubes material. Obviously; higher purity forms have more effective properties. Cost-per-gram values, however, are invariably higher than lower purity forms. [2]

Figure 2.66: The control room of the new Baytubes®

production facility in Laufenburg, showing the top of

the fluidized bed reactor. The facility has a capacity

of 30 metric tons annually. Market potential

estimates for carbon nanotubes (CNTs) in the

coming years are several thousand metric tons per

year. (Courtesy of Baytubes.)


47

Figure 2.67 _ illustrates how basic unit cost ranges for common Nanomaterials products

broadly compare to other materials. As with other high-performance materials that are used in composites, however, one should keep in mind that direct comparisons with truly bulk materials, such as steel, should be viewed in the light that quite small quantities of Nanomaterials may normally be actually used. Many actual products based on nanocomposites, for example, have only relatively low percentages (for example, 2% to 5%) of Nanomaterials by weight. Many Nano-based thin films or paints involve only small amounts as well and consequently can be competitively priced. On the other hand, the gross unit costs of many technologically sophisticated and high-value products currently involving the use of Nanomaterials or nanotechnologies are normally quite high. Interestingly, the current price of a very high end hearing aid that has a nanotechnology component is currently just under $1,000,000 per kilogram (mass: 2 grams, cost: $1800), and the price of a cobalt-chrome denture involving Nanomaterials is $90,000 per kg, based on a similar calculation (mass: 20 grams) thus the latter has costs similar to those of the hearing aid. Certainly this is suggestive of where many Nanomaterials are most likely to find markets. [2]

Figure 2.67: Material price in US$/kg for common engineering materials and for typical Nanomaterials.

Costs for Nanomaterials vary dramatically with the type of material, the degree of functionalization, and

special processing needs for inclusion in products.


48

2.5. Nanomaterials in Architecture Design: [2]

There are already many applications of

Nanomaterials in design and more are expected soon (see Figure 2.68). We look at these topics from the perspective of designers and within the larger cultural-socioeconomic context in which designers operate.

Making effective design application use of new

scientific findings that seemingly appear every day

within the Nanomaterials field is not as easy as might

first appear. Proposed products may never have been benchmarked against existing products. There might not be adequate test results to convince anyone of the efficacy of the product. Actual manufacturing processes for converting a science-based finding into implemental technology suitable for use in a commercial environment may either not be actually feasible or be cost-prohibitive. There may be legal or institutional barriers that

would prevent active consideration of a new product

or cause an interested developer to think twice before

proceeding:

1- There can be user resistance from sources that should have perhaps been anticipated but perhaps were not (e.g., environmental health hazards in using new materials).

2- Come from sources that simply could not have been easily anticipated a priori. The list can go on and on.

Questions surrounding the way an artifact or environment has been conceived, how it was made, and the materials of which it has been made have been a particular preoccupation of designers, engineers, and builders for ages. An understanding of the potential benefits and limitations of various materials is clearly evident in early works of art, architecture, and engineering (see Figure 2.69). Examples abound. Medieval builders are often said to have clearly understood the properties of stone, and they used this knowledge to help shape the arches and vaults of history’s great Romanesque and Gothic cathedrals. We thus need to keep in mind that the nature of our world of designed objects and environments is not dictated by a consideration of the technical properties of a material alone, no matter how fascinating they might be; but it is equally important to acknowledge their fundamental role we know that the introduction of new materials with improved technical properties has also led to innovative new designs (see Figure 2.70).

Figure 2.68: The Kurakuen house in Nishinomya

City, Japan, designed by Akira Sakamoto Architect

and Associates, uses a photocatalytic self-cleaning

paint—one of the many architectural products

based on Nanomaterials. (Courtesy of Japan

Architect)

Figure 2.69: The evolution of arches that act

primarily in compression only was related to the

inherent material properties of masonry, which can

carry large stresses in compression but little in

tension.

Figure 2.70: The introduction of materials such as

steel that can carry bending stresses involving both

tension and compressive stresses has allowed

designers to explore new shapes.


49

The best approach to understanding the use of

materials in design remains through an examination of

the benefits and limitations associated with the specific

properties of materials. For this initial discussion,

material attributes can be very broadly thought of in

terms:

• Technical properties that stem from the intrinsic characteristics of the material itself (its density and its mechanical, thermal, optical, and chemical properties).

• Perceptual qualities that stem from our senses (sight, touch, hearing, taste, smell).

• Culturally dependent qualities that fundamentally stem from the way our society or culture views materials.

The intrinsic characteristics of materials are dependent primarily on the fundamental atomic structure of the materials. Typical technical properties include failure strengths; elastic module values that relate deformations to stress levels, electrical conductivities, thermal conductivities, and a host of other measures related to the mechanical, optical, thermal, and chemical qualities of materials (see Figure 2.71). Clearly, these kinds of properties are of fundamental importance to an engineering perspective on the use of materials in the context of designing products or buildings, and we can expect that work in the Nanomaterials field can lead to dramatic improvements in these kinds of properties.

The perceptual qualities of a material relate to the way humans perceive them in terms of our basic senses. Visual qualities stem from a combination of specific characteristics such as transparency, translucency, opaqueness, reflectivity, and the texture of the surface. Tactile qualities

related to the sense of touch stem the texture of the surface whether it is rough or smooth, its relative hardness or softness, and the feeling of warmth or coldness experienced. In some design situations, the senses of smell or taste can be important as well. Certainly these qualities are directly related to the intrinsic properties and structure of a material.

2.5.1. Design Focus:

In thinking in more detail about how to use Nanomaterials in a design context, a first

consideration is simply to define what is being designed. In general, this research broadly addresses common products for everyday use as well as in architecture and related works. Ultimately, however, we will see that there are marked similarities in the basic design processes and issues present in each of these fields, despite the fact that there are also dramatic differences. [2]

Both products and buildings can also be generally thought of in terms of their constituent

environments, systems, and assemblies. It is here where material selection issues occur. Environments maybe an integral part of a design, such as spaces within a building, or they can define the external context within which a product operates. Systems and subsystems provide

Figure 2.71: Primary material characteristics.


50

specific functions (e.g., heat sources, lifting). Physical assemblies and subassemblies house the components of functional systems or otherwise provide support or enclosure functions. [2]

In general, as system and assembly complexities increase, problems related to the need to resolve conflicting design objectives invariably increase as well, as do problems associated with optimizing design solutions. [2]

Another important way of understanding how Nanomaterials and nanotechnologies fit into the broader design picture is via a close look at general design processes and their objectives. Many formal design processes proceed from a determination of design needs and requirements and move to the determination of needed material properties and subsequent material type selection. [2]

Every material that is used in the construction of a building has a history. Armed with

some knowledge about what materials are the most consumptive over their life cycles,

consumers can make wise choices that can influence the markets to change to suit their

preferences. [7]

- What makes a building material Environmental Sustainable? [7]

There are a number of different lists of criteria to define whether a building material is preferable environmentally. Ultimately, after consulting these lists to see what sorts of considerations need to be taken into account, it is up to the consumer to define what their values tell them is most important. Water efficiency is likely to be far more important to someone living in the desert than to someone living in a water rich environment. It will be important too for you to hear why different groups place priority on different criteria before you choose what is the most significant for you.

Some of the most common aspects of a product's environmental performance that are

considered by consumers include:

• Energy efficient and with low embodied energy.

• Made of renewable materials.

• Made of post-consumer recycled materials.

• Made of post-industrial recycled materials.

• Made of certified wood.

• Healthy for indoor air – low voc.

• Healthy for the atmosphere – no CFCs or HCFCs used in manufacturing.

• Non-toxic in use, production, or at end of useful life.

• Made of salvaged materials.

• Recyclable at end of useful life.

• Simple to install without dangerous adhesives, etc.

• Made near to the building site – low transportation impacts.

• Efficient/resourceful/reusable packaging.


51

2.6. The holistic application of Nanosurfaces in interiors: [1]

Nano functions have been employed in interior design only occasionally if at all, and more or less by chance. The schematic plans for a hotel room, a patient's room in a clinic or hospital and a bank branch demonstrate concepts for a general strategic approach to using Nano functions in interior design. The overall concept varies depending on the respective needs of the different uses. The spaces are optimized through the strategic use of Nanosurfaces with regard to aesthetic, economical and ecological concerns. Improved comfort and cost-effectiveness go hand in hand. Cost assessments should take account not only of the initial expenditure but also the follow-on costs, which are reduced considerably. Despite the fact that these are visionary concepts, they could already be realized today in this or a similar form.


52

2.7. Conclusion:

1- Nanomaterials are materials made from nanometer-scale substances has opened up possibilities for new and innovative functions. They can be used as coatings, insulations, air purifying or in product manufacture. [4]

2- In recent years, a relatively large number of products for architecture have been developed and brought to the market. They are mainly used for passive climatization of e.g. wall and ceiling components. Some more ambitious applications are now being tried following a phase of observation and testing in small projects. [4]

3- Various products with surfaces made of TiO2 and capable of changing reversibly their adhesion in response to UV light have been developed for architectural applications. By the choice of components used the products have no overall light-dependent hydrophilic properties but show a permanent hydrophobic effect. [4]

4- The materials chosen offer an overview of the Nanomaterials most suitable at the current time for use in architecture, interior architecture and design. [4]

5- Some of this “science fiction” is already real. Much more is a promise, but one in which considerable confidence can be placed. As with most major innovations, there are two principle obstacles to be overcome: [2]

The first: to develop a sufficiently deep understanding of behavior to establish both the good and the bad, the benefits and the hazards, of the nanoscale.

The second: is that of economics. Nanomaterials are expensive and will remain so, at least for some time. Finding ways to cushion the transition to economic viability needs thought.

Chapter Three

Future Applications of Nanomaterials in Architecture for Sustainable Development

3.1. Introduction. 3.2. Green Nanotechnology. 3.3. Nanomaterials in Sustainability and the Environment. 3.4. Nanomaterials in Sustainability and the Energy. 3.5. Conclusion.

Chapter Three Future Applications of Nanomaterials in Architecture for Sustainable Development

53

3. Future Applications of Nanomaterials in Architecture for Sustainable Development

3.1. Introduction:

Buildings and life in our buildings have changed over the last 25 years. Apart from a few exceptions, it is not spectacular buildings and housing types that define our times, it is above all the changes in building technology and automation. Through the development of innovative materials, products and constructions, the move to endow buildings with more functions, the desire for new means of expression, and ecological and economic constraints, it is now possible to design buildings that are clearly different from those of previous decades. [4]

In the future, the environment will interact with occupants in ways hardly imaginable today, creating what a 2005 United Nations report calls “an internet of things.” Tiny nanosensors embedded in building materials will soon be able to track movement and detect temperature changes, humidity, toxins, weapons—even money. Sensors will pick up on users' preferences and attributes, which will then trigger responses in the intelligent objects around them, dimming the lights, altering the temperature, or—as is already happening with “push” technology that marketers use to blitz cell phones—alerting them to nearby sales and events. [26]

Soon, the design and construction of buildings will incorporate a rich network of interacting, intelligent objects, from light-sensitive, photochromic windows to user-aware appliances. Buildings will not be static but will change constantly as their components continuously interact with users and each other. These dynamic environments will be almost organic in their ability to respond to changes, so architects will need to learn to design for change. [26]

As materials gain such transient features, architectural design and construction will evolve. By transforming the essential properties of matter, nanotechnology will be able to change the way we build. For instance, structures will be constructed from the bottom-up because materials like carbon nanotubes can self-assemble. [27]

Carbon nanotubes are a great example of how useful materials are being developed. This material is said to be one hundred times stronger than steel because of its “molecular perfection” as explained in the paper Year 2050: Cities in the Age of Nanotechnology by Peter Yeadon. In addition, because carbon atoms can bond with other matter; such material can be an “insulator, semi-conductor or conductor of electricity”. As a result, carbon nanotubes will have significant influence on the architecture industry as such materials can act as “a switchable conduit, a light source, and a generator of energy and even a conveyor of matter”. [27]


54

3.2. Green Nanotechnology:

Green nanotechnology is the development of clean technologies, to minimize potential environmental and human health risks associated with the manufacture and use of nanotechnology products, and to encourage replacement of existing products with new nanoproducts that are more environmentally friendly throughout their lifecycle. [27]

- Goals:

Green Nanotechnology has two goals: [27]

• Producing Nanomaterials and products without harming the environment or human health, and producing Nano-products that provide solutions to environmental problems. It uses existing principles of Green Chemistry and Green Engineering to make Nanomaterials and nanoproducts without toxic ingredients, at low temperatures using less energy and renewable inputs wherever possible, and using lifecycle thinking in all design and engineering stages.

In addition to making Nanomaterials and products with less impact to the environment, Green Nanotechnology also means using nanotechnology to make current manufacturing processes for non-Nanomaterials and products more environmentally friendly. For example, nanoscale membranes can help separate desired chemical reaction products from waste materials. Nanoscale catalysts can make chemical reactions more efficient and less wasteful. Sensors at the nanoscale can form a part of process control systems, working with Nano-enabled information systems. Using alternative energy systems, made possible by nanotechnology, are another way to "green" manufacturing processes.

• The second goal of Green Nanotechnology involves developing products that benefit the environment either directly or indirectly. Nanomaterials or products directly can clean hazardous waste sites, desalinate water, treat pollutants, or sense and monitor environmental pollutants. Indirectly, lightweight nanocomposites for automobiles and other means of transportation could save fuel and reduce materials used for production; nanotechnology-enabled fuel cells and light emitting diodes (LEDs) could reduce pollution from energy generation and help conserve fossil fuels; self-cleaning nanoscale surface coatings could reduce or eliminate many cleaning chemicals; and enhanced battery life could lead to less material use and less waste. Green Nanotechnology takes a broad systems view of Nanomaterials and products, ensuring that unforeseen consequences are minimized and that impacts are anticipated throughout the full life cycle.


55

3.3. Nanomaterials in Sustainability and the Environment:

Sustainable architecture is a general term that describes environmentally-conscious design techniques in the field of architecture. Sustainable architecture is framed by the larger discussion of sustainability and the pressing economic and political issues of our world. In the broad context, sustainable architecture seeks to minimize the negative environmental impact of buildings by enhancing efficiency and moderation in the use of materials, energy, and development space. Most simply, the idea of sustainability, or ecological design, is to ensure that our actions and decisions today do not inhibit the opportunities of future generations. [30]

Figure 3.1_shows some examples of sustainable building materials include recycled denim or blown-in fiber glass insulation, sustainably harvested wood, Trass, Linoleum, sheep wool, concrete (high and ultra high performance, roman self-healing concrete), panels made from paper flakes, baked earth, rammed earth, clay, vermiculite, flax linnen, sisal, seegrass, cork, expanded clay grains, coconut, wood fiber plates, calcium sand stone, locally-obtained stone and rock, and bamboo, which is one of the strongest and fastest growing woody plants, and non-toxic low-VOC glues and paints. [30]

Buildings are responsible for 50% of the world’s generation of CO2. How can design mitigate this alarming statistic and address the fact that climate change in general is threatening the future existence of mankind? Research and delivery of ways to avoid this catastrophe must be our primary aim (see Figure 3.2). [29]

There will be increasing challenges to designing a sustainable built environment over the next 100 years. The likely increase in global warming over the coming century means that designers will require greater creative skills and better understanding of building performance in order to ensure that low energy and passive buildings can continue to meet end-user needs and expectations.

Sustainability is defined as “the ability to provide for the needs of the world's current population without damaging the ability of future generations to provide for them”. A key aspect of sustainability is conservation through the efficient use of the resources that are tied up in the already built environment. As existing stock increases so will the need for effective maintenance and significant benefits will be offered by a realistic assessment of material lifetimes. Materials scientists have quantitative models which go from nanometers to millimeters and cover 6 length scales (e.g. pore network models to study the permeability of concrete). Engineers have models that go from tenths of millimeters to tens of meters and therefore cover about 6 length scales (e.g. structural analysis). Together they can, theoretically, cover 12 scale lengths and a model covering such a scale would be a powerful tool for service life predictions. [8]

Figure 3.1: Recycling items for building.

Figure 3.2: Flow of CO2 in an ecosystem.


56

“In the field of cement and its derivatives, sustainability will be a major issue. The control of the cement hydration … could lead to a new generation of products. These products will have a better ratio (of) property to mass, that means, the same or better property could be obtained with less material. Their production processes could be more environment-friendly. The same could be for other construction materials and the components made using them” [8]

3.3.1. Nanotechnology with Concrete and Steel:

CO2 emissions from the global cement industry are significant and they are increasing. The global cement industry produces around 1.4 tons of CO2 each year. This represents about 6% of the total worldwide man-made CO2 production.

Concrete is probably unique in construction in that it is the only material exclusive to the business and therefore is the beneficiary of a fair proportion of the research and development money from industry.

At the basic science level, much analysis of concrete is being done at the Nano-level in order to understand its structure using the various techniques developed for study at that scale such as Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM) and Focused Ion Beam (FIB). This has come about as a side benefit of the development of these instruments to study the nanoscale in general, but the understanding of the structure and behavior of concrete at the fundamental level is an important and very appropriate use of nanotechnology. Concrete is, after all, a macro-material strongly influenced by its Nano-properties and understanding it at this new level is yielding new avenues for improvement of strength, durability and monitoring.

A further type of nanoparticles, which has remarkable properties, is the carbon nanotubes (CNT) and current research is being carried out to investigate the benefits of adding CNT’s to concrete. The addition of small amounts (1% wt) of CNT’s can improve the

Figure 3.3: Helix of sustainability – the carbon cycle of manufacturing.

A- Concrete: [8]


57

mechanical properties of samples consisting of the main Portland cement phase and water. Oxidized multi-walled nanotubes (MWNT’s) show the best improvements both in compressive strength (+ 25 N/mm2) and flexural strength (+ 8 N/mm2) compared to the reference samples without the reinforcement. It is theorized the high defect concentration on the surface of the oxidized MWNTs could lead to a better linkage between the nanostructures and the binder thus improving the mechanical properties of the composite rather like the deformations on reinforcing bars.

The cost of adding CNT’s to concrete may be prohibitive at the moment, but work is being done to reduce their price and at such time the benefits offered by their addition to cementitious materials may become more palatable.

Steel has been widely available since the second industrial revolution in the late part of the 19th and early part of the 20th Century and has played a major part in the construction industry since that time. A total of 185m tones of steel are produced per year in the EU and steel benefits from its wide use in industries which neighbor construction (e.g. automotive) and therefore enjoys a healthy allocation of research funding. The construction industry can benefit from the application of nanotechnology to steel and some of the promising areas currently under investigation or even available today.

Current research into the refinement of the cementite phase of steel to a Nano-size has produced stronger cables. High strength steel cables, as well as being used in car tires, are used in bridge construction and in pre-cast concrete tensioning and a stronger cable material would reduce the costs and period of construction, especially in suspension bridges as the cables are run from end to end of the span. Sustainability is also enhanced by the use of higher cable strength as this leads to a more efficient use of materials.

Although carbon nanotubes (CNT’s) are an exciting material with tremendous properties of strength and stiffness, they have found little application as an addition to steel as their inherent slipperiness (due to their graphitic nature) makes them difficult to bind to the bulk material and they pull out easily, rendering them ineffective. In addition, the high temperatures involved in steel manufacture and the effects of this on CNT’s presents a challenge for their effective use as a composite component.

Two relatively new products that are available today are Sandvik Nanoflex (produced by Sandvik Materials Technology) and MMFX2 steel (produced by MMFX Steel Corp). Both are corrosion resistant, but have different mechanical properties and are the result of different applications of nanotechnology.

Traditionally, the tradeoff between steel strength and ductility is a significant issue for steel; the forces in modern construction require high strength, whereas safety (especially in seismic areas) and stress redistribution require high ductility. This has led to the use of low strength ductile material in larger sizes than would otherwise be possible with high strength brittle material and consequently it is an issue of sustainability and efficient use of resources. Sandvik Nanoflex has both the desirable qualities of a high Young’s Modulus and high strength and it is also resistant to corrosion due to the presence of very hard nanometer-sized particles in the steel matrix. It effectively matches high strength with exceptional formability and currently it is being used in the production of parts as diverse as medical instruments and bicycle components, however, its applications are growing. The use of stainless steel reinforcement in concrete structures has normally been limited to high risk environments as its use is cost prohibitive.

B- Steel: [8]


58

3.3.1.1. Carbon Nanotubes:

The current stars of the Nano-world are another variety of the fullerenes known as carbon nanotubes (CNT), or simply nanotubes for short, and were discovered in 1991 by Professor Sumio lijima at the electronics concern NEC in Tsukuba, Japan. [1]

Nanotubes consist of single-walled (SWNTs) or multiwalled (MWNTs) carbon tubes of rolled layers of graphite. [1]

They have a diameter of between one and a few nanometers and can be several nanometers long (see Figure 3.5). They have a tensile strength far in excess of steel, yet are flexible and lighter. [1]

Their thermal conductivity is also higher than any other known material, exceeding that of diamond. Their key properties - great strength coupled with low weight - are predestined for use in future composite materials. Nanotubes can act as semiconductors or as conductors. Their electric conductivity is excellent, and as such nanowires are of great interest for electronic applications such as minute circuits and a generally more efficient use of electricity (see Figure 3.6). [1]

Extremely stable, lightweight and conductive – ideal properties for a perfect raw material for the future. New application areas are constantly being discussed in the sciences and breakthroughs and new discoveries occur regularly. Nanotubes are always mixed with other materials or applied to surfaces. The company Hyperion Catalysis International, for example, mixes small quantities of electrically conductive nanotubes into plastics to facilitate electrostatic discharge. Plastics are likewise mixed with nanotubes to improve their mechanical properties considerably. [1]

The development of nanotubes is continually being optimized. The cost for their production has fallen significantly since the initial high cost of manufacture. With the development of the so-called "Baytubes" method, high-quality nanotubes can now be produced much more cheaply and in large quantities. Similarly, the NASA recently developed a method for the cost-effective mass production of nanotubes. [1]

Figure 3.4: One way in which chemists manipulatecarbon nanotubes is by creating nanotubesderivatives nanotubes that are decorated with extramolecules that give the tubes unique properties oract as chemical "handles" for further manipulation.

Figure 3.5: Single‐walled carbon nanotubes can beextruded to form macroscopic fibers.

Figure 3.6: This image shows a single carbonnanotubes isolated and enclosed in a molecule.Under particular conditions carbon nanotubes havebeen found to exhibit fluorescent properties. In thenear‐infrared range, light is absorbed and emitted.


59

Although nanotubes can now be produced comparatively economically, they are still too expensive for use in large quantities, for example as additives for concrete. In order to be practical for the mass market (Sustainable Economy), it is essential that they are to be obtained not only at a consistently high quality and secured availability but also at a sufficiently low price. Before the production of nanotubes can become feasible for the mass market, it must also overcome some hurdles with regard to purity. Nevertheless, it seems as if it is only a matter of time before these problems will be overcome. From then on, the way is paved for highly stable materials for the construction of bridges (e.g. ultra-strong concrete) or of skyscrapers. The NASA is using nanotubes in its research for a truly visionary project - an elevator into outer space! [1]

Nanotubes are currently the stars of the field of nanotechnology. A nanotube is simply an atom layer folded into a tube like shape one or a few nanometers in diameter. Nanotubes have several surprising features, such as the ability to give them metallic or semiconductor properties of electrical conductivity, among other properties currently under study. [3]

- Size: 0.6 to 1.8 nanometers in diameter. [3]

PHYSICAL PROPERTIES Single wall nanotubes A comparison

Density 0.77 to 0.81 oz/cu in (1.33–1.40 g/cu cm)

Aluminum has a density of 1.6 oz/cu in (2.7 g/cu cm)

Resistance to tension 6.5 million pounds per square inch (45 billion pascal)

Very tough steel alloys break at around 290,000 pounds per square inch (2 billion pascal).

Elasticity They can bend sharply and go back to their original shape without any damage.

Metals and carbon fibers break when subjected to similar tests.

Electric current capacity Estimated at 6.5 billion amperes per square inch (1 billion/sq cm).

Copper wires melt at approximately 6.5 million amperes per square inch (1 million/sq cm).

Field emission Can activate phosphates with 1 to 3 volts if the electrodes are spaced out at 0.00004 inch (1 m).

Tips of molybdenum require fields of 15 to 30 volts per foot (50–100 V/m) and have very short life spans.

Heat transmission It is predicted to be as high as 3,300 watts per foot per degree Fahrenheit (6,000 W/m/K) at room temperature.

An almost pure diamond transmits 1,800 watts per foot per degree Fahrenheit (3,320 W/m/K).

Thermal stability Stable even at 5,100° F (2,800° C) in a vacuum environment and at 1,390° F (750° C) in the air.

The electrical wires inside microchips melt at between 1,100° F (600° C) and 1,800° F (1,000° C).

Figure 3.7: The largest nanotube model in the world was produced by a team at Rice University in Houston, Texas.


60

- The Carbon Tower:

1- The Carbon Tower: Architecture Peter Testa.

Product Carbon Nanotubes. Sustainable Environmental Objective

Face the issue of the urban heat island Additions to the city’s urban tissue should therefore aim toward minimizing the thermal mass added, as well as employ a strategy for dealing with seismic vibration. [30]

Responding to these issues is the principle of tensegrity. Structures of this type are inherently material efficient and resilient, with tension and compression members sustaining each other in an equilibrated, rather than hierarchal, system. [31]

In this way the tensegrity system is interdependent force equilibrium. Mechanical stress is absorbed uniformly by every part of the system. While making tensegrity highly interesting as an architectural construct, dealing with its complexity is also what makes it scarcely implemented. [31]

Architects Peter Testa and Sheila Kennedy have very different practices, but both navigate the uncharted waters of innovative design through collaboration with manufacturers, multidisciplinary interaction, and the adaptation of nascent technologies. "The complexity of contemporary buildings is an enormous achievement, but we need to question how we came to the point of building with such complexity. We believe we need to rethink how we assemble buildings." These might seem like strange words coming from architect Peter Testa, who, with his partner, Devyn Weiser, has designed a carbon-fiber tower, a complex undertaking that proposes to build a high-rise tower out of composite materials. According to Testa, the willingness to use complex computer modeling tools (see Figure 3.9) will allow the design of new buildings, materials, and products that just might transform the building industry. [32]

The lure for many manufacturers is scale, an advantage not lost on Testa. The carbon tower project (see Figure 3.8) was envisioned with that strategic thinking. "The [construction] industry isn't completely fixed. If one finds applications for materials that are provocative and at a big enough scale, it is possible to engender new divisions of industry," says Testa. The ultimate measure of an innovation is when it becomes a reality. [32]

Figure 3.8: A percep onal 3D image of the proposedcarbon tower by Peter Testa.

Figure 3.9: Computer aided engineering design forTesta's carbon tower.


61

The project is a prototype 40 story skyscraper made entirely of composite materials, mostly carbon fiber. Such man-made composites, which also include better-known materials like fiberglass and Kevlar, are increasingly used in industry and for consumer goods—in everything from airplane fuselages to tennis rackets—because they are strong, lightweight, and easily molded into an almost endless variety of shapes. They’re also slowly making their way into highway bridges and other civil engineering projects. [33]

Testa’s carbon tower is the product of ongoing research in computer-aided engineering and material science; as a result, its design seems to change on a weekly basis (see Figure 3.10). But the basic form is not especially complex. Imagine, first of all, a cylindrical building 40 stories high. Then picture that cylinder strung together by 40 carbon-fiber strands, about 1 inch wide and nearly 650 feet long, which are arrayed in a helicoidally, or crosshatch, pattern. Filling in the structure between floors is an advanced glass substitute. A pair of ramps on the exterior of the building offers circulation and further stabilizes the structure. [33]

That, in simplified form, is the carbon tower. Perhaps the most striking thing about it is that every major element in the building, including the floors and the exterior ramps, is made of some kind of composite material—there is no steel, concrete (apart from the foundations), or conventional glass. Yet just as important is the structural use of continuous carbon strands, which are woven to form a structure that distributes its loads over its entire surface (see Figure 3.11). [33]

The 24 strands will be fixed into shape by something called a robotic pultrusion machine, which Testa envisions climbing up the structure like a spider and weaving the strands on the side of the tower as it’s built. “You just bring a bundle of fibers and some plastic to the site, and then you manufacture the building right there,” he says. “Each of the strands will have its own machine.” [33]

The tower aims to reconfigure all three central elements of contemporary skyscraper design: structure, circulation, and heating-and-cooling systems. Indeed the combination of the growing sustainable-design movement and the World Trade Center’s collapse has made skyscrapers a target for double-edged critique: Not only do they treat the earth horribly on a day-to-day basis, but they’re not reliable for humans in a structural crisis, either. [33]

Figure 3.11: A longitudinal section of the CarbonTower.

Figure 3.10: Computer aided engineering design fordesigning and forming carbon fiber of Testa towers.


62

3.4. Nanotechnology in Sustainability and the Energy:

The term “Energy” is wide-ranging and represents one of the most important physical state variables. For example, energy sources can be divided into primary energy and secondary energy: [9]

• Primary: energy comes from the direct exploitation of energy sources as they exist in nature (gas, coal, oil, wood …).

• Secondary: energy is generated from primary energy through a transformation requiring technical means (electricity …).

Another key aspect of sustainability is the efficient use of energy. In the EU, over 40% of total energy produced is consumed by buildings. Insulation is an obvious solution to reduce some of this energy use; however, limited space for installation is a major problem for building renovation. Micro and nanoporous aerogel materials are very good candidates for being core materials of vacuum insulation panels but they are sensitive to moisture. This risk is not acceptable for high performance thermal insulation and the next challenge is to develop a totally airtight wrapping, taking into account the foil and the welding. As a possible remedy, work by Aspen Aerogels has produced an ultra-thin wall insulation which uses a nanoporous aerogel structure which is hydrophobic and repels water so it is mould free. [8]

“Nanotechnology is an enabling technology that is opening a new world of materials functionalities, and performances. But it is also opening new possibilities in construction sustainability. On one hand it could lead to a better use of natural resources, obtaining a specific characteristic or property with minor material use. It can (also) help to solve some problems related to energy in building (consumption and generation), or water treatment to mention only a few matters” [8]

That’s why, in order to meet the Kyoto commitments, new policies are being considered that would speed up the deployment of more efficient and cleaner technologies, achieve energy savings and promote switching to less carbon-intensive fuels. For example, the European Commission has identified 3 main objectives of Community energy policy that take account of the environmental sustainable dimension: [9]

The most advanced nanotechnology projects related to energy are: storage, conversion, manufacturing improvements by reducing materials and process rates, energy saving e.g. by better thermal insulation, and enhance renewable energies sources. More specifically in products such as batteries, manufacturing catalysts, fuel cells, solar cells, and strong lightweight materials, among others. There are noteworthy developments in nanotechnology and its relevance to the energy field and most are anticipating advances and solutions to the sustainability, pollution and renewable energy issues. [9]

• To promote energy efficiency/saving. • To increase the share of production and use of cleaner energy sources. • To reduce the environmental impact of the production and use of energy sources.


63

3.4.1. Energy Production: [9]

Nanotechnology offers most promises for renewable energy technologies. On the one hand, the precise control of matter at atomic and molecular level is a requirement for renewable such as cost effective solar PV, which can be made cheaper with a thin layer of active material on a cheap substrate such as plastic, which is much cheaper and more lightweight then glass. Glass is the cost-limiting factor in PV and therefore with glass it will not really be possible to make a great PV breakthrough or be cost competitive.

On the other hand renewable energy technologies could have financial supports and public incentive in the first years. Many EU member states are working towards this direction. The main goal for renewable energy in the long run is to be cost competitive!

For example, building solar cells containing nanolayers or nanorods could significantly increase the amount of electricity converted from sunlight by using nanostructured surfaces as more effective light absorbers (variation of the absorbing wavelengths by quantum dots) and Nano porous electrodes. These same Nanomaterials are combined with plastic electronics to develop semiconductor polymer photovoltaics and they are especially advantages for their lightweight and flexible properties. There is already research work being completed on flexible solar cells and the potential users include campers, mountain climbers to NASA spacecraft.

Fuel cells benefits from electrodes and electrolytes with nanostructured and therefore enlarged surface of thin films of nanometer thickness.

Microturbines are a new type of combustion turbine used for stationary energy generation applications. They are small combustion turbines, approximately the size of a refrigerator, with outputs of 25 kW to 500 kW, and can be located on sites with space limitations for power production. Some microturbines use nanotechnology in their component parts.

Figure 3.12: Working principle of a solar cell.


64

3.4.2. Thin-film Solar:

Thin-film solar technologies often use non-silicon semiconductor materials including copper, indium, gallium and selenium (CIGS) to create photovoltaic cells that convert sunlight into electricity (see Figure 3.13). Without the expensive and often sparse silicon, the cells are cheaper in terms of materials costs. The non-silicon materials can also be printed on flexible or light substances, which can create new applications for solar. But thin films, aren’t yet as efficient as silicon-based solar, and can remain pricey due to their high production costs. [35]

- Nanosolar Production Process: Step by Step

1. Semiconductor Nanoparticles: Because the targeted film is micron-thin, the nanoparticles that create it are even smaller. Nanoparticles (see Figure 3.14) are 20nm in size, equivalent to 200 atoms in diameter. We have developed a proprietary formula for which kinds of nanoparticles produce the best solar cells, developed high-yield proprietary techniques for fabricating exactly these kinds of nanoparticles.

2. Nanoparticle Ink: The ink we have developed is based on proprietary chemistry suitable to disperse our nanoparticles into a high-quality dispersion which is stable and non-agglomerating and produces high-quality coatings.

3. Printed Foil: The Nanoparticle ink is coated onto a specially-prepared proprietary alloy of metal foil using high-throughput coating/printing techniques that work in normal atmosphere, with no clean room required (see Figure 3.15).

4. Cell Formation: The cell is completed by adding fingers and a back contact capable of efficiently carrying current with minimal optical and resistive loss. The solar-electric foil is then slit and sheeted into pieces to form individual cells. Cells can be cut to any size. Cells are individually tested and sorted into performance bins based on electrically matched characteristics.

5. Panel Assembly: Cells are assembled into circuits and laminated into panels. By using cells only from matched performance bins, mismatch losses within a panel are minimized to less than 0.1%, improving performance and reliability. Our solar panel assembly factory is automated to produce one solar panel every ten seconds on one line of production (see Figure 3.16). [36]

Figure 3.13: Thin‐film Solar Cell.

Figure 3.14: Nanoparticles produce the best solarcells.

Figure 3.15: Metal foil.

Figure 3.16: Solar Cell Panel.


65

The holy grail of solar cost and capital efficiency has long been unlocking the key to how one could deposit a thin film of a semiconductor—100x thinner than a silicon wafer—using a printing process—100x faster than conventional high-vacuum deposition—and create an efficient, durable solar cell. [36]

The US National Renewable Energy Laboratory (NREL) has created thin film solar panels that are very close to competing with their more traditional silicon-based cousins. [37]

It is estimated that thin film producer Nanosolar's cells are 6.7% efficient. At that level, just a 3.3% increase in efficiency to 10% would allow each cell to capture 50% more energy, reducing the price per watt by 33%. [37]

The Nanosolar Utility Panel™ is the industry’s first solar electricity panel specifically designed and developed for utility-scale system deployment. [37]

A thin-film panel that stretches conventional expectations on power, current, system voltage, and mounting span, it enables solar power plant deployments with an industry-lowest total-system cost (see Figure 3.17). [37]

- Mounting Labor:

An independent third party performed time-clocked tests in a field in Germany, where trained teams of installers mounted a full table of First Solar and a full table of Nanosolar panels. The Nanosolar Utility Panel™ required 30% less mounting labor time and up to 85% less cabling time (see Figure 3.18). [37]

Figure 3.18: Panel size drives balance‐of‐system cost savings on mounting labor and panel‐to‐panel cabling.

Figure 3.17: Nanosolar combines a host of innovations to deliver adistinct overall cost reduction.


66

- Utopia one - Dubai: [34]

1-Utopia one - Dubai: Architecture cesar bobonis-zequeira, ivan perez-rossello & teresita del valle. Product Nano-cell technology (thin photovoltaic film). Sustainable Environmental Objective

Using thin photovoltaic film to gain energy for run services in tower.

Cesar bobonis-zequeira, Ivan perez-rossello and teresita Del valle designed 'utopia one' (see Figure 3.19) for the Dubai tall emblem structure competition in Zaabeel Park.

The tower and its elements are composed of materials that resemble a smooth sculptural piece that are integrated into the park. The base behaves as a single unit housing the programmed spaces, entry areas and existing walkways. Form creates a courtyard intended for gatherings and general leisure. Conceptually, the structure reacts to the gravitational forces that act upon it and gives the allusion of hovering above the ground. The tower grows from the base element becoming an extension of the sculpture giving way to the observation deck. The elevator is constructed of glass all around and encased inside a shaft with a glass exterior to permit views to the outside as one rises. The observation deck (oculus platform) is formed by a ring that supports a glass floor intended to give the sensation of flight (see Figure 3.21).

Nano-cell technology will be integrated to the exterior skin of the building, providing a portion of the energy to run the elevator systems, HVACs systems and electrical systems. Nano-cell technology is a thin photovoltaic film bonded to metal surfaces (see Figure 3.20). Heat sensitive glass reacts to the sun’s position and controls the heat gain in the glassed surfaces. Water management features will reuse grey water for irrigation and provide water for the HVACs systems.

Figure 3.20: 'utopia one' power, through Nanotechnology.

Figure 3.19: the Utopia One tower.

Figure 3.21: Interior View of Utopia One tower.


67

3.4.3. Organic light-emitting diode(OLED):

An Organic Light Emitting Diode (OLED), is a light-emitting diode (LED) whose emissive electroluminescent layer is composed of a film of organic compounds. This layer of organic semiconductor material is formed between two electrodes, where at least one of the electrodes is transparent. [38]

The OLED devices which are manufactured on glass and metal substrates are extremely thin, lightweight and come in various sizes from 25 cm2 up to 225 cm2 active areas (see Figure 3.22). Depending on the substrate material and device structure chosen, OLEDs can be transparent, have a diffuse appearance or behave like a mirror in the off state. [39]

- Advantages:

• Some of the future advantages of the OLEDs are the possibilities to provide thinner, lower-powered and more flexible screens for uses in products such as cameras, PDAs, cell phones, laptops and computer monitors. [9]

• Probably the biggest advantage of the OLEDs over LCDs is the fact that OLEDs emit their own light, while LCDs require a light source. The leads to cost advantages over LCDs, as OLEDs would use less power, take up less space by eliminating the need for a light source. [9]

OLEDs are a new and attractive class of solid-state light sources and they are emerging as a compelling candidate to replace conventional lighting systems for large area illumination. Organic LEDs generate a diffuse, non-glaring illumination with high color rendering. They are flat, thin, and have the potential to serve as efficient large area light sources. OLEDs are instant-on, can be dimmed and can be produced on substrates of basically any shape. This high level of flexibility in terms of design and application make them highly appealing for designers, manufacturers and consumers. Furthermore, as a highly efficient light source, OLEDs have the potential to achieve substantial energy savings. [10]

- Tiling Architecture:

Most types of lamps generate light as a ‘spot’, except for the fluorescent lamp which can be described as a linear light. Except for electroluminescent films – which are not suitable for general illumination due to low efficacy – the creation of area emitters is only possible by means of clustering point or linear light sources in combination with diffusers, light guides or other optical aids. [10]

Figure 3.22: A 3.8 cm (1.5 in) OLED display.

Figure 3.23: Structure of a typical bottom emitterOLED device. The ITO (indium tin oxide) anode andthe OLED stack are transparent. In on‐state light iscoupled out through the substrate. In off‐state thereflective metal cathode causes the mirror effect.


68

Ceiling systems are mechanical support structures (see Figure 3.24) which can be found in many variations. Most common are systems with raster patterned surfaces. They are made of metal substructures which support various shapes and sizes of ceiling tiles. One can also find “open” systems which are not made up of joined ceiling tiles, but rather of suspended „grid“plates with a specific height of the grid bars. The latter ones can exhibit shapes like squares or honeycombs. The raster patterned ones can be divided into several principles, such as T-systems, Z-systems, clipping systems, linear grid systems or others. [10]

Different from ceiling systems floor and wall tiling is much more diversified in terms of dimensioning. Shape-wise, there is still a preference for square tiles, but any other shape can be found as well. The edge length is usually smaller than pitches of ceiling systems. While 60 cm which is fairly typical there, for tiles 60 cm is a kind of maximum dimension rarely used (see Figure 3.25). [10]

600 mm x 600 mm, 300 mm x 300 mm or 150 mm x 150 mm. The single OLED tile should be a little smaller to reserve space for mechanical fixing. [10]

As, unlike common lighting systems, the OLED will become a part of the surrounding room surfaces and detaches itself from the luminaire, as a creative object which is additionally positioned in a room. It is luminaire and material in one. Its modular form creates a structure and therefore a characteristic appearance, which when used as a planar application can also have a considerable influence on the room even when it is switched off. [10]

In order to increase creative freedom and to enable an optimum integration into the architecture, one can suggest further geometric basic forms (see Figure 3.26), which can be combined with each other. [10]

Figure 3.24: Schematic cross‐sections of a Z‐system (left), a T‐system (middle) and a clippingsystem (right).

Figure 3.25: Guidelines for OLED module pitches of1.5M and mul ples thereof.

Figure 3.26: Basic geometric shapes.


69

At the end design recommendations for future OLED tiles, OFF-state mode and color temperature could be derived to these conclusions: [10]

• Decorative elements in form of specially designed tiling architectures are more accepted in residential areas, whereas working areas seem to be more critical in the selection of tile sizes and tile shapes.

• Squared tile sizes with a side length of 15 cm were preferred the least though they seem the first approach from standardization and component integration point of view.

• Aesthetical preferences in e.g. tile shape, color temperature, etc., were partially influenced by luminance levels. Generally spoken, higher luminance levels had a stronger effect on aesthetical preferences than tile shapes.

• Within both working and residential areas OLEDs should hardly be noticed in off state mode. A neutral white appearance is recommended though the problems in creating a realistic simulation should be taken into account. The results of this particular study are the least reliable ones.

• We could find a clear preference for lower color temperatures (3000 K and 4000K) of future OLED light sources. Generally speaking, the color temperature 6500 K was clearly refused.

It is very important to ensure the market acceptance of future OLED designs at an early stage. This can be done focusing on two aspects: [10]

• The first aspect is an architectural one, it deals with existing standards and norms in terms of built-in dimensions of current lighting fixtures (e.g. for ceilings) and other building materials such as wall or floor tiles which can be substituted by light emitting OLED tiles.

• The second aspect deals with pure aesthetics and needs to identify a mainstream taste among end users. If this mainstream taste can be technically transferred into product design, a high market acceptance can be easily anticipated.

Figure 3.27: Four room models with different scenarios for comparative evaluation placed next to each other. In this case the colortemperature of light was altered which was subject of evaluation in another study.


70

3.4.4. Nanosensors:

Nanosensors are any biological, chemical, or sugery sensory points used to convey information about nanoparticles to the macroscopic world. Their use mainly includes various medicinal purposes (see Figure 3.28) and as gateways to building other nanoproducts, such as computer chips that work at the nanoscale and nanorobots. Presently, there are several ways proposed to make nanosensors, including top-down lithography, bottom-up assembly, and molecular self-assembly.[45]

Products most commonly involve using nanosensors to build smaller integrated circuits, as well as incorporating them into various other commodities made using other forms of nanotechnology for use in a variety of situations including transportation, communication, improvements in structural integrity, and robotics. Nanosensors may also eventually be valuable as more accurate monitors of material states for use in systems where size and weight are constrained, such as in satellites and other aeronautic machines. Nanosensors in building components create smart environments that constantly adapt to their environment and users. [45]

- Economic Impacts: [45]

Though nanosensor technology is a relatively new field, global projections for sales of products incorporating nanosensors range from $0.6 billion to $2.7 billion in the next three to four years. They will likely be included in most modern circuitry used in advanced computing systems, since their potential to provide the link between other forms of nanotechnology and the macroscopic world allows developers to fully exploit the potential of nanotechnology to miniaturize computer chips while vastly expanding their storage potential.

First, however, nanosensors developers must overcome the present high costs of production in order to become worthwhile for implementation in consumer products. Additionally, nanosensor reliability is not yet suitable for widespread use, and, because of their scarcity, nanosensors have yet to be marketed and implemented outside of research facilities. Consequently, nanosensors have yet to be made compatible with most consumer technologies for which they have been projected to eventually enhance.

Figure 3.28: A nanosensor probe carryinga laser beam (blue) penetrates a livingcell to detect the presence of a productindicating that the cell has been exposedto a cancer‐causing substance.


71

- Off the Grid: Sustainable Habitat 2020:

1- Off the Grid: Sustainable Habitat 2020 - China: Architecture Philips’s Design Probes. Product Nanosensors. Sustainable Environmental Objective

Using nanosensors to maintain & control the building for low energy and good environment.

- Design:

Today, our habitat is very dependent on the international grid of energy & water. Energy crisis, clean water shortage, global warming and environmental pollution are worldwide problems. Understanding cities as dynamic and ever-evolving eco-systems can help us to formulate strategies for a sustainable urban future with Nanotechnology. The whole project (see Figure 3.29) is based on the brief to develop sustainable housing for urban megalopolis in China in 2020. [46]

This is exploring the integration of electronics and bio chemical functionalities into the inert material of the built environment (Nanosensors). The design of the concept fundamentally changes the current approach to buildings and habitat. This future habitat shifts from the current state where the building surfaces are benign inert ‘dumb’ materials only used for construction and shielding purposes to sensitive functional skins that are ‘alive’ and act as membranes to harness energy. A membrane creates a strong link between the exterior and interior of the habitat and used as a transporter collecting and channeling the elements of air water and light - from the outside feeding into the inside space. will supply the habitat with all necessary sources to be able to live off the grid. [46]

- Nanosensors Sustainable Features:

The active skin of a building reacts to sunlight and automatically moves into the most efficient position to channel light and generate energy (see Figure 3.30).

By collecting and channeling the natural light no electricity will be needed during the day for lighting.

Bringing natural light into our homes will not only save energy but also provide all the advantages for health and well being.

Figure 3.29: Off the Grid: Sustainable Habitat 2020.

1- Light: [47]

Figure 3.30: The active skin of building moves andcollect light to channel and generate energy thencontrol it with the grid without electricity.


72

The active skin of the building reacts to the wind. By channeling air and wind through the skin of the building energy will be generated and the air will be filtered to provide clean air inside the building (see Figure 3.31).

Compressed and dissipated through funnels, the air will also be cooled for natural air-conditioning. Outside air is cleaned and stripped of CO2 before being exhausted from the building.

The active skin of the building reacts to the rain and collects and channels rainwater into the habitat. By catching moisture from the air the facade collects water even in dry periods (see Figure 3.32).

Through purification, filtration and reuse, water will be used in a closed loop and fresh water consumption would be optimized.

2- Air: [47]

3- Water: [47]

Figure 3.31: The active skin of building reacts withwind to channel and generate energy and filteringair and cooling it.

Figure 3.32: The active skin of building reacts torains and collects water to be used in closed loop.


73

Human waste and other organic waste will be transformed into biogas energy (see Figure 3.33).

The biogas can be used for heating and cooking as well as providing hot water for washing.

4- Waste: [47]

Figure 3.33: The active skin of building collecthumane waste to convert in biogas used in heating,cooking and washing.


74

3.5. Conclusion:

1- We are standing at the threshold of the next generation of buildings: buildings with various degrees of high technology, which are extremely ecological in their behavior through the intelligent use of functionally adaptive Nanomaterials, products and constructions and are able to react to changes in their direct or indirect surroundings and adjust themselves to suit. [4]

2- Depending on the future popularity of use of Nanomaterials and the visible effects on our buildings, our picture in relation to our built environment will change from what we are used to seeing as architecture. [4]

3- Carbon nanotubes—sheets of graphite just one atom thick, formed into a cylinder—are not only 50 times stronger than steel and 10 times lighter, they are transparent and electrically conductive to boot. Nanotubes are already the building blocks for hundreds of applications, used to reinforce concrete and deliver medication to individual cells. [26]

4- Privacy, sustainability, and security are just a few of the issues that will be profoundly affected by Nanotechnology and Nanomaterials. As threats from terrorism and even from natural forces like hurricanes rise, we will utilize the strength of nanotubes to make our buildings more secure. [26]

5- Solar cells containing nanolayers or nanorods could significantly increase the amount of electricity converted from sunlight. Nanostructured materials or nanocomponents are used in future or emerging energy producing technologies including solar photovoltaics and hydrogen conversion. [9]

6- Nanosensors can monitor temperature, humidity, and airborne toxins, vibration, decay and other performance concerns in building components, from structural members to appliances, will be increasingly incorporated in the planning of building components, and many buildings and structures will be retrofitted with nanosensors. [18]

75

GENERAL CONCLUSION

1- Nanotechnology is disruptive and offers the possibility of great advances whereas conventional approaches, at best, offer only incremental improvements. [8]

2- Nanotechnology is the opposite of the traditional top-down process of construction, or indeed any production technique, and it offers the ability to work from the “bottom” of materials design to the “top” of the built environment. [8]

3- There are three main issues that might prevent the widespread use of the nanotechnology: [8]

• Lack of vision to identify those aspects that could be changed through its use. • Lack of skilled personnel. • Level of investment.

4- By creating the Nano Living System we reduce CO2 emissions by simply decreasing the size of the living space. However, in order to have the least amount of environmental impact we do much more than just reduce the size of a living space. We create efficient, intelligent, hybrid small living areas with flexible spaces that require lower amounts of energy to operate, therefore using fewer natural resources. [41]

5- Nanomaterials will produce buildings lighter, smaller and more robust which will save in the cost of construction and saves a flat earth for future generations and maintain the natural materials and natural terrain of the mountains, plains, forests and all of this supports the idea of sustainability.

6- Taken into account in the design of Nanomaterials biometric system for humans, animals and plants, the ecological system of natural phenomena and climate.

7- The new characteristics of Nanomaterials affect the achievement of sustainability and bio-characteristics (biomaterials in terms of functional form) as to achieve the highest benefit to humans and the environment and the economy.

RECOMMENDATIONS

1- Nanotechnology is a complex and deep subject and it is next to impossible to grasp for those who are not actively involved, therefore, awareness of research done can only be increased by educating both students and professionals through easily digestible information made available through universities, relevant institutions, journals and other sources. [8]

2- Interest in nanotechnology science education to achieve the benefits gained from it economically, environmentally and socially.

3- The social, ethical, environmental and health effects of nanotechnology should be openly and thoroughly investigated and discussed and yet they offer great potential benefits for both comfort and the efficient use of energy. [8]

4- The development of cleaner, cheaper and more efficient processes requires an interdisciplinary effort involving various technological fields among them, nanotechnologies and Nanomaterials are identified as having the potential for a major impact on the energy system. [9]

76

LIST OF REFERENCES

- E-Books: 1- Leydecker, Sylvia. Nano Materials in Architecture, Interior Architecture and

Design. BirkhauserVerlag AG, 2008. 2- Michael F. Ashby, Paulo J. Ferreira, Daniel L. Schodek. NanoMaterials,

NanoTechnologies and Design. An Introduction for Engineers and Architects, Elsevier Ltd, 2009.

3- Nanotechnology. Encyclopedia Britannica. 2008. Encyclopedia Britannica Online. Retrieved 04 Aug. 2008 http://www.britannica.com/EBchecked/topic/962484/nanotechnology.

4- Ritter, Axel. Smart Materials in architecture, interior architecture and design. Birkhäuser, Berlin, 2007.

5- Johansen John M. Nanoarchitecture: A New Species of Architecture. Princeton Architectural Press New York, 2002.

- Reports:

6- Insulation of a mixed use building with 7 storeys in Munich with VIP. 7- Johanna, Sands. Sustainable Library Design. 8- nanoforum.org, European Nanotechnology Gateway, Nanoforum report:

Nanotechnology and Construction. November 2006. 9- nanoforum.org, European Nanotechnology Gateway, Nanoforum report:

Nanotechnology helps solve the world's energy problems. April 2004. 10- The OLED100.eu project: Three aesthetical perception case studies. 11- Nano material science. Nanotechnology: A Brief Introduction, Luisa filipponi &

Duncan Stherland Interdisciplinary Nanoscience center (INANO) University of Aarhus, Denmark h p://www.nanocap.eu/Flex/Site/Download.aspx?ID=2256.

- Web links:

12- What’s Nano? http://en.wikipedia.org/wiki/Nano- . Retrieved October, 2009. 13- A virtual discovery journey into the worlds of micro and Nano cosmos

http://www.nanoreisen.de/ . Retrieved October, 2009. 14- Nanotechnology http://en.wikipedia.org/wiki/Nanotechnology . Retrieved October,

2009. 15- Nanomaterials http://en.wikipedia.org/wiki/Nanomaterials . Retrieved October, 2009. 16- Fullerenes http://en.wikipedia.org/wiki/Fullerene . Retrieved October, 2009. 17- Inorganic Nanoparticles http://en.wikipedia.org/wiki/Nanoparticle . Retrieved October,

2009. 18- NanoArchitecture and Construction http://www.politicsofhealth.org/wol/2008-3-

30.htm . Retrieved October, 2009. 19- Carbon Nanotubes in Architecture http://nanoarchitecture.net/ . Retrieved October,

2009. 20- The Future of Architecture with Nanotechnology

http://sensingarchitecture.com/1347/the-future-of-architecture-with-nanotechnology-video/ . Retrieved March, 2010.

21- Introduction about Nanotechnology http://www.nano.org.uk/whatis.htm#Intro . Retrieved March, 2010.

22- Introduction about Nanomaterials http://www.nano.org.uk/nano/whatisNEW3.htm#Materials . Retrieved March, 2010.

77

23- http://www.sabrycorp.com/co/2010/ (SabryCorp_brochure). Retrieved March, 2010. 24- http://science.nationalgeographic.com/science/space/universe/nanotechnology.html.

Retrieved March, 2010. 25- Green Nanotechnology http://en.wikipedia.org/wiki/Green_nanotechnology . Retrieved

March, 2010. 26- http://www.architectmagazine.com/curtain-walls/the-nano-revolution.aspx . Retrieved

October, 2009. 27- http://sensingarchitecture.com/523/nanotechnology-and-new-materials-for-architecture/ .

Retrieved April, 2010. 28- http://www.nanotechbuzz.com/50226711/variable_mood_lighting_for_walls_and_ceilin

gs_with_nanotubes.php . Retrieved April, 2010. 29- http://www.richardrogers.co.uk/render.aspx?siteID=1&navIDs=1,3,1179 . Retrieved

April, 2010. 30- http://en.wikipedia.org/wiki/Sustainable_architecture . Retrieved April, 2010. 31- http://challenge.bfi.org/application_summary/193 . Retrieved March, 2010. 32- http://archrecord.construction.com/innovation/2_Features/0310carbonfiber.asp .

Retrieved February, 2010. 33- http://www.metropolismag.com/story/20030201/carbon-fiber-future . Retrieved March,

2010. 34- http://www.designboom.com/weblog/cat/9/view/6490/utopia-one-dubai-tall-emblem-

structure.html . Retrieved March, 2010. 35- Thin-Film Solar http://earth2tech.com/2007/12/19/faq-thin-film-solar/. Retrieved

March, 2010. 36- Thin-Film Solar http://www.nanosolar.com/. Retrieved March, 2010. 37- Thin-Film Solar http://www.nanosolar.com/technology. Retrieved March, 2010. 38- OLED http://en.wikipedia.org/wiki/Organic_LED . Retrieved April, 2010. 39- OLED http://www.oled-a.org/press_details.cfm?ID=41 . Retrieved April, 2010. 40- http://www.nanowerk.com/nanotechnology/introduction/introduction_to_nanotechnolog

y_6.php . Retrieved April, 2010. 41- http://www.nanolivingsystem.com/index.php . Retrieved May, 2010. 42- http://www.archicentral.com/the-nano-towers-by-allard-architecture-17754/. Retrieved

May, 2010. 43- http://www.nano.uts.edu.au/about/australia.html . Retrieved May, 2010. 44- http://nanoventskin.blogspot.com/. Retrieved May, 2010. 45- Nanosensors http://en.wikipedia.org/wiki/Nanosensor. Retrieved May, 2010. 46- http://www.design.philips.com/probes/projects/sustainable_habitat_2020/index.page.

Retrieved May, 2010. 47- http://www.yatzer.com/postDetails.php?post=1095. Retrieved May, 2010.

78

ملخص الرسالةتسلط الرسالة الضوء على التطور الملحوظ في الفترة األخيرة من تقدم في مجال التكنولوجيا بصوره متسارعة مما

ومن أهم هذه التطورات الحديثة هو التطور في علوم تكنولوجيا النانو .يستلزم مواآبه هذا التسارع الرهيب في العلوم التكنولوجيةالتي أصبحت من أهم العلوم الحديثة التي ترتبط ارتباطا وثيقا بحياة اإلنسان واألنشطة والمجاالت المتعددة في الحياة وذلك بسبب

تكنولوجيا النانو في ظهور عالج حديث لعالج دخول : مجال الطب: صغر تلك المواد وخواصها الفريدة ومن أمثله تلك المجاالتومواد تعمل على الحفاظ على في ظهور مواد غير قابله للخدش ومواد تقوم بتنظيف نفسها: مرضى الخاليا السرطانية، مجال المواد

مارة ومواد البناء الخ، ومن الجدير بالذآر هو ارتباط تلك التكنولوجيا وظهورها في مجال الع... ظل عصر األستدامه في الطاقةمما أعطى فرص جديدة إلظهار أفكار مختلفة وتطور في التصميم واإلنشاء مثل ظهور مواد مثل الكربون فيبر الذي يتميز بمتانة

وسوف تشهد هذه . الخ... أآثر من المعدن وخفه وزنه، ومواد في الدهانات تنظف نفسها أو غير قابله للخدش أو تنقى الهواءمن مجتمع العولمة الى مجتمع 21وسيكون لها تأثير على تغير مجتمع القرن ال تطورا رهيبا في السنوات القادمةالتكنولوجيا

.المعلومات والمعرفة

شرح مفهوم إلى متطرقةأجزاء يتم من خاللها عرض الموضوع بصوره علميه متسلسلة ثالثةوقد تم تقسيم الرسالة إلى لعمارةامجال في المتنوعةوخصائصها وتكلفتها والتطبيقات والعمارةبالنانو وعالقتها بمواد البناء المتعلقةتكنولوجيا النانو والمواد

:يلي، ونلخصها فيما وعمليه األستدامه بالبيئةوعالقتها

ةه يبدأ البحث في توصيل مفهوم آلممع التطور المستمر للتكنولوجيا وظهور علوم حديث :مفهوم تكنولوجيا النانو -1نانو ومقياسها ووحداتها ومع هذا الصغر المتناهي لتلك المواد وخصائصها المتميزة ظهرت تكنولوجيا النانو

وظهور مواد وانعكاسها على العمارة واستخداماتها المتعددة في جميع المجاالت وظهورها في مجال العمارة والبناء .جديدة نتطرق إليها في الفصل الثاني

ن والتطرق إلى خواصها م وطرق تكوينها وتصميمها هذا الجزء يتم شرح ما هو مفهوم تلك الموادفي :مواد النانو -2

وتوضيح تأثيرها في مجال العمارة وتأثيرها من ناحية توفير الطاقة وعالقتها بالبيئة . كوينناحية المقياس والتالتطرق إلى تكلفه هذه المواد والتكلفة والحفاظ عليها وعالقتها بالتصميم وإمكانية استخدامها، وبناء على هذا تم

وتم عرض مختلف التطبيقات لمواد النانو في العمارة وأثارها. الناتجة أيضا عن استخدامها على المدى البعيدمن حيث مواد الدهانات والمواد العازلة ومواد تعمل على تنقيه الهواء وأيضا وخصائصها واستخاماتها المتنوعة

.حماية من الحريق وأشعه الشمس واالستخدامات المتعددة لها أيضا في التصميم الداخلياستخداماتها في ال مفهوم األستدامه وعماره النانو الخضراء واظهار العالقة الوثيقة هذا الجزء تم عرض في: تطبيقات مواد النانو -3

. عالقتها بالبيئة وتوفير مصادر الطاقةالستخدام تكنولوجيا النانو ومواد النانو وتأثيرها على األستدامه فى العمارة وآربون نانوتيوبس -1: وتتمثل فيالبيئة وقد تم عرض بعض األنواع المستخدمة فى عملية توفير الطاقة ومعالجة

)Carbon Nanotubes (تتميز بقوه أآثر من المعدن وخفيفة الوزن وتستخدم في تطبيقات متعددة وهناك هى وواستخداماتها المتنوعة ) Thin-film Solar(الخاليا الشمسية الرفيعة -2خدامها، تصورات مستقبليه أيضا الست

وحدات -3 ،بالطاقة ليتم استهالآها في المبنى واالحتفاظتوفير الوتفوقها على الخاليا الشمسية العادية وتعمل على وتتميز بتوفير الطاقة وشدة والتى تستخدم فى األضاءة بدال من الوحدات التقليدية ) OLED(األضاءة الصغيرة

التغيرات الظواهر والتى تستخدم ) Nanosensors(حساسات النانو -4ضاءة والعديد من المميزات األخرى، األالفيزيائية التى تحث فى البيئة وتحولها الى اشارات وتستخدم فى رصد عوامل بيئية والحد من التلوث وفى اداره

.عمليه األستدامة البيئية المبانى وتوفير الطاقة وتساعد فى

واستخدام مواد وهو توضيح مدى أهميه تكنولوجيا النانو في العمارة هذه الرسالةونصل من هنا إلى الهدف الرئيسي من اإلمكانيات المتعددة وإيضاحتأثيرها على توفير الطاقة والحفاظ على البيئة وتوفير مبدأ األستدامه وإظهارالصغر المتناهيةالنانو

.ويحقق مبدأ األستدامة البيئةتصميم ال يضر إلىنصل لكيلمواد وتكلفتها على المدى البعيد الستخدام هذه ا

�0�� ا!=�اف

�� ا��ل إ��اه�� / ا4��ذ ا��آ�ر� ��)��) ...................... �!�� ور��

�� ا�� ا��ر� ، أ�$�ذ ا��رة ا��$#�غ ) ا-�,��ر� ، آ*� ا��.

اد ا�� وا��رة�

"��رة ا�� ا��ا��"

�� *�

�&�� ,�زم �&�� ( ��

ل �� در#� %&��

��#�� ا� ��

�� ا�� ا��ر�

ا(�ن �0�� ا��/.� وا�&�- �� ا��

�� ا��ل إ��اه�� / ا4��ذ ا��آ�ر� ��)��) ...................... �!�� ور��

�� ا��، أ�$�ذ ا��رة ا��$#�غ ) ا��ر� ا-�,��ر� ، آ*� ا��.

�45ًا(�� 2�رق ا��0�د / ا4��ذ ا��آ�ر ...................... (

�� ا�� ا��ر� ، أ�$�ذ ا��رة ا��$#�غ ) ا-�,��ر� ، آ*� ا��.

�45ًا(9�د� 8�� ا��7ادى / ا4��ذ ا��آ�ر ...................... (

�� ا�� ا��ر� ، أ�$�ذ ا��رة ا��$#�غ ) ا-�,��ر� ، آ*� ا��.

وآ�7 ا�� را��ت ا�� وا�6&ث

#�� ا!��ر�� –آ�� ا� ��

إ�� ل ��: ا�9�6�� . د.أ

اد ا�� وا��رة�

"��رة ا�� ا��ا��"

��

�� اا��م ا�� ا��ر� #��" ا!��ر�� – � ��ت ا��

ا��)�ء ��را��ت ا��رة ��&%ل �� در#�

��#�� ا� ��

�)

ا� �� ا��ر��

*� ��

�� زم ��

��2010

Date post:	14-May-2018
Category:	Documents
Upload:	lamtuyen
View:	217 times
Download:	4 times

NANOMATERIALS & ARCHITECTURE A SCIENTIFIC …api.ning.com/files/zJEntOuSjcPOSPKM1vDsdrMca7... · A...

Documents