2. Introduction
• Nanomaterials are defined as materials with at least one external
dimension in the size range of approximately 1-100 nanometers.
• Nanotechnology deals with building and using materials, devices,
machines etc. at the nanometer scale making use of their unique
properties.
3. Scale of Nano systems
• Nano means 10-9 or one billionth of a unit
• Eg: A human hair is about 60,000 nanometers in diameter.
4. Classification of Nanostructured Materials (NSMS)
• NSMS include wide variety of materials such as meals, metal oxides,
semiconductors, ceramics, polymers, fullerenes and carbon
nanotubes.
• The most popular mode of classification is based on the number of
dimensions, which are not confined to the nanoscale range.
(˂ 100 nm)
5. Zero-Dimensional Nanomaterials (0D)
• These are materials wherein all the dimensions are measured within
the nanoscale. (i.e., no dimensions are larger than 100 nm)
7. Two-Dimensional Nanomaterials (2-D)
• In these materials, two of the dimensions are not bound to the
nanoscale.
• Eg: nanofilms, nanolayers, nanocoatings etc.
8. Three Dimensional Nano materials (3-D)
• These are bulk materials and are not confined to the nanoscale in any
dimensions.
• Eg: composite materials, materials of multinanolayers
9. Nano Materials vs Bulk Materials
• When the particle size decreases (i.e., bulk material changes to nano
materials) number of atoms on its surface increases. A size deduction
to 3 nm increases the surface atoms to 50%. This leads to enhanced
surface phenomenon.
• When the diameter of particles equals the wave length of electron
wave function, quantum confinement effect occurs. This leads to
increase the energy difference between energy levels and energy
band gap. It leads to change in optical and electronic properties.
• Eg: gold nanoparticles appear red whereas the bulk materials is
yellow.
10. Synthesis of Nanomaterials
• The two synthesis approach are: top-down and bottom-up
• Thin film preparation is bottom-up method whereas nanolithography
is bottom-up approach.
11. Applications of Nano Materials
• In Biology and Medicine:
• Detection of tumour cells
• To deliver cancer drugs
• Nanochips for biochemical analysis
• Nanorobots as therapeutic agents
12. • In Electronics:
• In microelectronic industy
• In Food Packing:
• As nanosensors and disinfectant
• In Energy Sector:
• In rechargeable batteries and in solar cells
13. Toxicology of Nanomaterials
• Some nanofabrication methods uses toxic raw materials or produce
toxic by-products.
• Nanotoxicology is a field of research that deals with the study of
effect of engineered nanoparticles on living systems.
14. Health issues with nano materials
Brain
Lungs
Gastrointestinal system
Skin
Lymphatic System
Alzheimer’s and Parkinson’s disease
Cancer, asthma, bronchitis
Blood pressure, thrombus, vasoconstriction
Dermatitis, auto-immune disease
sarcoma
