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SHRIRAM INSTITUTE FOR INDUSTRIAL RESEARCH19, UNIVERSITY ROAD, DELHI-110 007
Dr. R. K. KHANDAL
DIRECTOR
NANOTECHNOLOGY: SCOPE, CHALLENGES & OPPORTUNITIES
Scope of nanotechnology Definition Need Dimensions Domain Features
Challenges of nanotechnology Process technology Manufacture Disposal
Opportunities for nanotechnology Industries Teaching Science & Technology
Path Forward
OUTLINE
Nanomaterials:
Materials consisting of particles of the size of nanometer
Volume= Surface area x thickness
For a given volume:
Surface area thickness
More atoms at surface than in the bulk
Extraordinary activity
Scope: Definition
Systems Need
Emulsion Macro Micro
Dispersion Coarse Fine
Solution Colloid
Solubilization
Scope: Need
Need to create the disperse phase as continuous and as fine as possible for homogeneity with the dispersing phase
SCOPE : DIMENSIONS
What Happens Dimensions
Particle size More from less
Surface area Enhanced coverage
Activity Novel products
Efficiency Improved performanceper unit mass
Maximum possible benefits from minimum possible inputs
Effecting changes through and at atomic scale
SCOPE : DOMAIN
Keywords Domain
Particle size Distribution in thecontinuous phase
Modification of surfaces Interfacial tensions
Surface Interface
Rising volume fraction Homogeneity of phases
of dispersing phase Domain of Nanotechnology
Liquid : Liquid Gas : Liquid
Solid : Liquid Gas : Solid
Surfaces and interfaces involving different phases
Scope: Features Size- dependent properties
As the scale goes down, the activity rises mainly due to the lowering distances at which the interparticle interactions occur leading to evolution of energy.
Emulsion
High surface energy, Non-homogeneous unstable
Thermodynamically
ExtremelyHigh
Irreversible
System Scale Activity RemarksMixtures >micrometer Low
Suspension
Dispersion
micrometer Medium Kinetically stable
unstableMicroemulsionSolubilised
nanometer ModeratelyHigh stability probable
Thermodynamic
Macromolecular angstrom High
MolecularAtomic
Very High
Nuclear
Spontaneous
atomic
sub-atomic
Thermodynamically stable
Basis for new materialsSource of energy
Process of making Nanomaterials
Process steps Inputs
Macro
Micro
Nano
Challenges: Process Technology
Challenge: To have a process that can convert macro materials into nano materials spontaneously & with minimum efforts
Energy
Bulk
Sugar cube
Nano
Dissolved sugar/salt
Bulk
Salt
Manufacturing Nanomaterials
Challenge: Manufacture
Input
Process
Output
Suitable Raw materials
Technology
Material for desired application
Challenges : • Identification and selection of suitable raw materials• Scale up of process of making nanomaterials
Challenge: Disposal
Nanomaterials are supposed to be hyperactive materials
In contact with living systems, they are expected to react
Cannot be disposed off like other materials
Challenges : Disposal ways Understanding of Toxicity Complete dossier of their degradability,
etc. without any effect on the environment
Opportunities: Nanomaterials for Industries
NANOPARTICLE
Electronics
Multiuse
Chemical Industries
DefenceOpticsCosmetics
Medical/Biology
Solar Cells
Sensors
Electrocatalysis
Photocatalysis
For any application, nanotechnology is a blend of the science of physics, chemistry and biology. Field of optics has seen a lot success with nanotechnology; coatings and drug delivery systems are an upcoming field now.
Potential applications of Nanomaterials
13
Nanomaterials: Organic (Carotenoids)
Problem
• Carotenoides form coarse crystals that are
– insoluble in water
– sensitive to light and air
Solution
• Formation of nanoscaled micronizates
• Stabilization by properly selected protective colloid
ββ-Carotene-Carotene Protective colloidProtective colloid
Nanoparticles, water dispersibleNanoparticles, water dispersible
250 nm250 nm250 nm250 nm
14
Nanomaterials: Inorganic
Nanomaterials: Organic (Colorants)
MACRO NANONANO MACRO
Nano colorants exhibit better solubilization and dispersion
DYES PIGMENTS
Nano-Structured Colorants
ORGANIC DYE
INORGANIC PARTICLES
Paints & Coatings Nanocomposites
GlassTextiles
Nanopigments
Bio-nanomaterials
Bones
Cartilage
Teeth
Targeted drug delivery
MACRO
MICRO
NANO
DNA Sequencing: macro to micro to nano
FUTURE OF NANOTECHNOLOGY
Structuresizes
2040 year1960 1980 20200.1 nm
0.1 µm
0.1 mm
Nano
Micro
Macro
Integrateduse of
biological principles,physical laws
and chemical know-howComplex chemistry
Electrical engin.
Electronics
Micro-electronics
Material design
Supramolecularchemistry
Quantum effectsCell biology
Molecularbiology Functional
molecule design
Applicationsof
nano- technology
bottom up bottom up
top down
top down
Chemistry
Coatings,cleaning agents,
composite materials,textiles,
cosmetics,displays
Physics
Biology
2000
THANK YOU