Post on 23-Dec-2015
transcript
Dr. Kamal K. TahaAssociate Professor of Physical
ChemistryDean CAIS
U of B
Introduction to Nanotechnology
DefinitionNanotechnology, shortened to “nanotech”, is the study of the controlling of matter on an atomic and molecular scale. Generally nanotechnology deals with structures sized between 1 to 100 nanometer in at least one dimension and involve developing materials or devices within that size.
How small is Nano - small?
Units in nanometers (µm)
Compared to Human Hair
A Human Hair is about 100,000µm wide
At small size physical observation simply changes. It is no longer governed by the classical picture.
Nano-structures & SensitivityAs objects are scaled down the ratio of the surface to volume increases sharply. This makes surface effects more pronounced.
Isolated small size electrode will possesses high sensitivity due to non-linearity effects.
Chemical Synthesis
LOW temperature methods Hydrothermal chemical growth of ZnO
Different Nano-structrures Obtained by controlling the reaction parameters
Nanotechnology spans many Areas
NANOTECHNOLOGY
Information
Technology
Mechanical Eng. &
Robotics
Biotechnology
Transportation
NationalSecurity &Defense
Food andAgriculture
Energy &Environment
Aerospace
AdvanceMaterials & Textiles
Medicine /
Health
NANOTECHNOLOGY
Information
Technology
Mechanical Eng. &
Robotics
Biotechnology
Food andAgricultureAerospac
e
AdvanceMaterials & Textiles
Medicine /
Health
Energy &Environment
NANOTECHNOLOGY
Information
Technology
Mechanical Eng. &
Robotics
Biotechnology
Food andAgricultureAerospac
e
AdvanceMaterials & Textiles
Medicine /
Health
NANOTECHNOLOGY NationalSecurity &Defense
Food andAgriculture
Energy &Environment
Aerospace
AdvanceMaterials & Textiles
Medicine /
Health
NANOTECHNOLOGY
Food andAgricultureAerospac
e
AdvanceMaterials & Textiles
Medicine /
Health
Energy &Environment
NANOTECHNOLOGY
Information
Technology
Food andAgricultureAerospac
eMedicin
e /Health
Mechanical Eng. &
Robotics
NANOTECHNOLOGY NationalSecurity &Defense
Food andAgriculture
Energy &Environment
Aerospace
Medicine /
Health
NANOTECHNOLOGY
Food andAgricultureAerospac
eMedicin
e /Health
Energy &Environment
NANOTECHNOLOGY
Information
Technology
Food andAgricultureAerospac
eMedicin
e /Health
Biotechnology
Mechanical Eng. &
Robotics
NANOTECHNOLOGY NationalSecurity &Defense
Food andAgriculture
Energy &Environment
Aerospace
Medicine /
Health
NANOTECHNOLOGY
Food andAgricultureAerospac
eMedicin
e /Health
Energy &Environment
NANOTECHNOLOGY
Information
Technology
Food andAgricultureAerospac
eMedicin
e /Health
Transportation
Biotechnology
Mechanical Eng. &
Robotics
NANOTECHNOLOGY NationalSecurity &Defense
Food andAgriculture
Energy &Environment
Aerospace
Medicine /
Health
NANOTECHNOLOGY
Food andAgricultureAerospac
eMedicin
e /Health
Information
Technology
Food andAgricultureAerospac
eMedicin
e /Health
Information
Technology
Mechanical Eng. &
Robotics
Information
Technology
Biotechnology
Mechanical Eng. &
Robotics
Information
Technology
Transportation
Biotechnology
Mechanical Eng. &
Robotics
Information
Technology
NationalSecurity &Defense
Transportation
Biotechnology
Mechanical Engineering
/Robotics
Information
Technology
Nanosized Iron for Groundwater Remediation:Smaller sized iron particles More complete reduction of chlorinated hydrocarbons
Absorbents for selective removal of pollutants • Teabag catalysts for de-stenching• Use high surface area Cu-ZnO catalysts to absorb S - compounds
End-of-pipe management and cleanup of pollution
Treatment & Remediation
Iron Treatment Walls…
Used in groundwater treatment for many years. Iron chemically reduces organic and inorganic environmental contaminants. Currently involves granular or “microscale” iron ( 50 m or 50,000 nm).
and Nanotechnology
Nanosized iron enhances the reaction. Enhanced further by coupling with other metals (Fe/Pd)* on the nanoscale. Nano Fe0 is more reactive and effective than the microscale. Smaller size makes it more flexible -- penetrates difficult to access areas. * Elliot and Zhang ES&T 2001, 35, 4922-4926
Kamat, P.V, et al. J.Phys.Chem. B 2002, 106,788-794.
Nanosized zinc oxide (ZnO) “senses” organic pollutants indicated by change in visible emission signal.
Sensing capability means that the energy-consuming oxidation stage only occurs when the pollutants present.
“Sense and Shoot” Approach to Pollution
Treatment
“Sense and Shoot” Approach to Pollution
Treatment
The ZnO “shoots” the pollutants via photocatalytic oxidation to form more environmentally benign compounds.
Multifunctionality and “smartness” is highly desirable for environmental applications.
Dual role of ZnO semicondouctor film as a sensor and photocatalyst
>300 nm
UV
Drug Delivery
Targeting Ligands
Liposome's
Governments Expenditure in Nanotech.
Western Europe : USD 669 Million
Japan : USD 810 Million
U. S. A. : USD 774 Million
Asia : USD 800 Million
AcknowledgementsTOKTEN-Sudan;Dr. Omer Nor;Institute for Technical Research –NCR Omdurman Ahlia University Future university University of Elneelain