Download The World of Nano.

The World of Nano.
Physics ACE by Sin Ming Da 4S425
What is Nano?

Nano, similar to kilo, is a prefix for
measurement scales.

1 nanometer is 1 x 10-9 meters.

But how small is that?
What is Nano?

To match the width of a human hair,
it would take eight hundred particles of
100 nanometres each placed side by side!
Source:http://www.understandingnano.com/introduction.html
Nanotechnology

Defined as the study and use of
structures between 1 nanometre and 100
nanometres in size.

But, with particles of such minute size
which can’t be seen by the naked eye and
the conventional microscope, how do
scientists study nanotechnology?
History of Nanotechnology

Got started in the early 1980s when the
Scanning Tunneling Microscope(STM) was
invented, which led to the discovery of
carbon nanotubes and fullerenes.
http://www.youtube.com/watch?v=fToTFjwUc5M
View of Gold atoms under a STM
Development of Nanotechnology

As scientists realized about the uses of
nanomaterials (which will be discussed
later), nanotechnology reached a peak in
the 90s and 21st Century.

The Atomic Force Microscope(AFM or
SFM) was invented shortly after the
invention of STM.
http://www.youtube.com/watch?v=87BQiFCkf9s
What happens in the Nano World?

Nanoparticles are particles that have one
dimension that is 100 nanometres or less
in size.

The properties of many materials change
when they become nanoparticles!
Gold which does not glitter?

When gold is shrank into nanoparticles,
its color changes too!
Why?

Nanoparticles have a greater surface area
per weight than larger particles, causing
them to be more reactive to certain other
molecules, and becoming another type of
substance.
Uses of Nanomaterials – Carbon
Nanotubes
One of the most accomplished products
discovered in nanotechnology.
 Due to the presence of strong covalent
bonds between the carbon atoms, hey
exhibit extraordinary strength and unique
electrical properties, and are efficient
thermal conductors.
 Often an important subject in the field of
material science.

Uses of Carbon Nanotubes

Everyday items like clothes and sports
gear to combat jackets and space
elevators – Due to its mechanical
strength.
Paper Batteries

The nanotubes are aligned on a piece of
cellulose.

The nanotubes act as electrodes, making
the storage device conduct electricity.

The paper battery integrates all of the
battery components in a single structure,
making it more energy efficient.
Vessel for Drug Delivery

The nanotube’s versatile structure can be
used for localized drug delivery in and
around the body – useful in treating cancer
cells.

Nanotubes can be filled with a drug and
delivered to specific areas where a chemical
trigger can release the drugs from the
nanotube.

More efficient than chemotherapy.
Solution to Water Pollution
Nanoparticles can be used to convert the
contaminating chemical through a
chemical reaction to make it harmless.
 Studies have shown that this method can
be used successfully to reach
contaminates dispersed in underground
ponds and at much lower cost than
methods which require pumping the
water out of the ground for treatment.

Solution to Water Pollution
For example, iron nanoparticles can be
used to clean up carbon tetrachloride
pollution in ground water.
 Also, nanoparticles can also be used to
absorb radioactive particles in ground
water.

Nanoelectronics

Using MEMS techniques to control an
array of probes whose tips have a radius
of a few nanometers.

These probes are used to write and read
data onto a polymer film, with the aim of
producing memory chips with a density of
one terabyte per square inch or greater.
Nanoelectronics

Building transistors from carbon
nanotubes to enable minimum transistor
dimensions of a few nanometers and
developing techniques to manufacture
integrated circuits built with nanotube
transistors.
Fuel
Nanotechnology can address the shortage
of fossil fuels such as diesel and gasoline
by:
 Making the production of fuels from low
grade raw materials economical.
 Increasing the mileage of engines.
 Making the production of fuels from
normal raw materials more efficient.
Fuel

They do all of these by increasing the
effectiveness of catalysts.

Catalysts made from nanoparticles have a
greater surface area to interact with the
reacting chemicals than catalysts made from
larger particles.

The larger surface area allows more
chemicals to interact with the catalyst
simultaneously, which makes the catalyst
more effective.
Fuel

This increased effectiveness can make a
process such as the production of diesel
fuel from coal more economical, and
enable the production of fuel from
currently unusable raw materials such as
low grade crude oil.
Cosmetics

Sunscreens.

The traditional chemical UV protection
approach suffers from its poor long-term
stability. A sunscreen based on mineral
nanoparticles such as titanium dioxide offer
several advantages. Titanium oxide
nanoparticles have a comparable UV
protection property as the bulk material, but
lose the cosmetically undesirable whitening
as the particle size is decreased.
Heavy Industry

Aerospace

Lighter and stronger materials will be of immense use to
aircraft manufacturers, leading to increased
performance. Spacecraft will also benefit, where weight
is a major factor. Nanotechnology would help to reduce
the size of equipment and thereby decrease fuelconsumption required to get it airborne.

Hang gliders may be able to halve their weight while
increasing their strength and toughness through the use
of nanotech materials. Nanotech is lowering the mass
of supercapacitors that will increasingly be used to give
power to assistive electrical motors for launching hang
gliders off flatland to thermal-chasing altitudes.



Construction
Nanotechnology has the potential to make
construction faster, cheaper, safer, and more varied.
Automation of nanotechnology construction can
allow for the creation of structures from advanced
homes to massive skyscrapers much more quickly and
at much lower cost.
Refineries
Using nanotech applications, refineries producing
materials such as steel and aluminium will be able to
remove any impurities in the materials they create.
Vehicle manufacturers
Much like aerospace, lighter and stronger materials
will be useful for creating vehicles that are both faster
and safer. Combustion engines will also benefit from
parts that are more hard-wearing and more heatresistant.
Implications of Nanotechnology
Researchers have discovered that silver
nanoparticles used in socks only to
reduce foot odour are being released in
the wash with possible negative
consequences.
 Silver nanoparticles, which are
bacteriostatic, may then destroy
beneficial bacteria which are important
for breaking down organic matter in
waste treatment plants or farms.

Implications of nanotechnology

A study at the University of Rochester
found that when rats breathed in
nanoparticles, the particles settled in the
brain and lungs, which led to significant
increases in biomarkers for inflammation
and stress response.

Would that happen to human beings too?
Conclusion

However, nanotechnology has proved to
be extremely useful, and has a lot of
applications.
References
http://www.understandingnano.com/nano
particles.html
 http://en.wikipedia.org/wiki/List_of_nanot
echnology_applications
 http://science.howstuffworks.com/nanotec
hnology.htm
