History of nanoscience, Nanomaterial Dimensions, why small is good, surface area to volume ratio, top down and bottom up technique and physical and chemical synthesis technique and future application.

1. Submitted by: Preeti choudhary
Roll No.= 17/MAP/016
M.Sc.(Applied Physics)

2. Content
 What is a Nanoparticle?
 Nanomaterial Dimension
 Why small is good?
 Surface area to volume ratio
 Top down & Bottom up Approach
 Applications

3. Talk given to the American Physical Society, 1959
There’s plenty of Room at the Bottom

4. What is a Nanoparticle ?
• Nanoparticle is any material having atleast
one of its dimensions in the range of 1-
100nm.
• Nano– Derived from a Greek word “Nanos”
meaning Dwarf or small.
• A nanometer is one billionth of a meter
(10ˉ⁹ m).
• Nanometer scale range from approximately
100 nm to 1nm.
Ref: Introduction to Nanoscience : S. M. Lindsay, Oxford, 2010.

5. Ref: Written by lusia filipponi and duncan sutherland interdisplinary nanoscience centre (iNANO) Aarhus university, denmark
september 2010
• Nanoscience: It is the study of phenomena
and manipulation of materials at atomic,
molecular and macromolecular scales, where
properties differ significantly from those at a
larger scale.
• Nanotechnology: It can be define as the
design, characterisation, production and
application of structures, devices and systems by
controlling shape and size at the nanometer
scale.

6. Fig 1: From macro-materials to atoms. Nanomaterials and nanodevices that
are of interest in nanotechnologies are in the lower end of the scale(1-
100nm)
nanoscale
• Ref: lusia filipponi and duncan sutherland interdisplinary nanoscience centre (iNANO) Aarhus university, denmark september
2010

7. Ref: Written by lusia filipponi and duncan sutherland interdisplinary nanoscience centre (iNANO) Aarhus university, denmark september 2010
Fig 2: Comparison between human fingernail & men’s beard growth.

8. Fig 3: Density of states g(E) VS Energy (E) for four quantum structures.
Ref: Source: Introduction to Nanoscience : S. M. Lindsay, Oxford, 2010
. Quantum Mechanics for Nanostructures : Vladimir V. Mitin, Dimitry I. Sementsov & Nizami Z. Vagidov, Cambridge, 2010.

9. Why small is good?
• Faster
• Lighter
• Can get into small spaces
• Cheaper
• More energy efficient
• Different properties at very small scale

10. Properties of a Nanomaterial
• A property describes how a material acts under certain
conditions.
• Types of properties:
 Optical (e.g. color).
 Electrical (e.g. conductivity).
 Physical (e.g. melting point).
 Chemical (e.g. reaction rate).
Ref: Written by lusia filipponi and duncan sutherland interdisplinary nanoscience centre (iNANO) Aarhus university, denmark
september 2010

11. Surface to Volume Ratio Increases
Ref: http://www.uwgb.edu/dutchs/GRAPHIC0/GEOMORPH/SurfaceVol0.gif
[1] S. Shibata, K. Aoki, T. Yano and M. Yamane, Journal of solgel science and Technology, 11, 279, (1998).
• As surface to volume ratio
increases
• A greater amount of a
substance comes in
contact with surrounding
material.
• This results in better
catalysts, since a greater
proportion of the
material is exposed for
potential reaction.

12. What are the possible approaches to making Nanomaterials
and Nanotechnologies?
• There are basically two routes: a top-down
approach and a bottom-up approach.
• The idea behind the top-down approach is the
following: An operator first designs and controls
a macroscale machine shop to produce an exact
copy of itself, but smaller in size. Subsequently,
produce an exact copy of itself, but smaller in
size. Subsequently, this downscaled machine
shop will make a replica of itself, but also a few
times smaller in size.
• The concept of the bottom-up approach is that
one starts with atoms or molecules, which build
up to form larger structures.
• H. Hahn, Nanostructured Materials, 9, 3, (1997)

13. Synthesis Methods
Chemical method
• Sol-Gel Method
• Micelle and Inverse Micelle
Method
• Condensation method
• Sol Method
• Hydrothermal Method
• Solvothermal Method
Physical method:
• Thermal decomposition
• Plasma arcing
• Evaporative deposition
• Electron beam physical vapour
deposition
• Sputter deposition
• Cathodic arc deposition
• Pulsed laser deposition

14. Application of Nanomaterials

15. Future Applications
Electronics
Coatings
 Fuel Cells
Water filters
Composites
Drugs
Cancer Detection & Treatment

16. Thank-you for listening.