Nanotechnology is the use of very small
particles of material. A nanometer is a
billionth of a meter.
Nanotechnology is not a new science and
it is not a new technology. It is rather an
extension of the sciences and technologies
Nanotechnology will make most exiting
products quite a bit more powerful and
The nanotechnology promises a rapid
improvement of technology at low cost
and high convenience.
Computers will compute faster, materials
will become stronger and medicine will
cure more diseases
The nanotechnology has potential of
developing and fabricating dangerous
weapons, drugs in large quantity.
At this moment the main limitation is the
high costs of nanotechnology. Also
concerns with the environmental effects.
Nano particle: It is defined as a
particle with at least one
dimension less than 200nm.
Nano composite : It is produced by
adding Nano particle to a bulk
material in order to improve the
bulk material’s properties.
Fig.Nanotube on a
small cement grain
Carbon Nano Tubes(CNT)
They are cylindrical with nanometer diameter.
They have 5 times the Young’s modulus and 8 times
(theoretically 100 times) the strength of steel.
• Titanium dioxide is a widely used white pigment.
• When incorporated into outdoor building
materials can substantially reduce
concentrations of airborne pollutants.
• Additionally, as TiO2 is exposed to UV light, it
becomes increasingly hydrophilic ,thus it can be
used for selfcleaning windows.
Concrete is stronger, more durable and more
Steel is made tougher .
Glass is self-cleaning.
Paints are made more insulating and water
As we know, Concrete is a mixture of
cement, sand(fine aggregate), coarse
aggregate and water.
As concrete is most usable material in
construction industry it’s been require to
improve its quality.
Concrete is, after all, a macro-material
strongly influenced by its nano-properties.
(ECC) used to
repair a bridge
CNTs in concrete
The addition of small amounts (1% wt) of
CNT’s can improve the mechanical properties
of samples consisting of the main Portland
cement phase and water.
Oxidized multi-walled Nano tubes (MWNT’s)
show the best improvements both in
compressive strength (+ 25 N/mm2) and
flexural strength (+ 8 N/mm2) compared to
the samples without the reinforcement.
These have found increasing application in civil
Due to super-elastics properties, the elastic
deformation of SMAs is followed by a large
increase of strain under an almost constant
stress. After unloading, only elastic strain
recovers and the residual stain can be removed
Fig(a) Tendon buckles during
Fig(b)Tendon recovers after
Fig(a) Concrete cracks upon
Fig(b) Crack is closed up
Fig. 7mm thick concrete wall
• The barely visible blue-green area at the top of
this X-ray shows that very few chloride ions (in
green) penetrate into the concrete. Infiltrating
chloride and sulphate ions cause internal structural
damage over time that leads to cracks and weakens
• This can be removed rather than change the size
and density of the pores in concrete, it would be
better to change the viscosity of the solution in the
concrete at the microscale to reduce the speed at
which chlorides and sulphates enter the concrete.
Human Hair 75 µm
Nanotechnology: Size and Scale
Plant and Animal Cells
Atoms Cooper, 2001
In 1959 Richrad Feynman
presented ideas for creating
Nano scale machines
introduced the term
1980s, development in this field was
greatly enhanced with advances in
Top-down Approach Bottom-up Approach
Creating Nano-scale materials
by physically or chemically
breaking down larger materials
Assembling Nano materials
atom-by-atom or molecule-by
molecule (self assembling)
Three distinct aspects
Ex : Electronic &
Ex : Nano bots,
All materials &
considered from a
Ex : Universal
Nano powders - building blocks of nano materials
(particles less than 100 nm in size)
store large amounts of H2
Nanoparticles of gold for
The scale of
(sensors, fuel cells,
„cross bar latches‟
(tiny Nano devices)
(small devices that
contain a tiny
droplet of free electrons)
Ex. Nano biotechnology
2001 2005 2010 2020
Agrifood applicatinos currently in
passive to early “active” stage
Ex: Delivery of DNA
Ex: Nano tube
sensors to detect
chemicals or food
Ex: Prevent or
2006 - Sri Lanka‟s National
Nanotechnology Initiative (SLNNI)
2008 Establishment of
NANCO (Pvt) Ltd
Sri Lanka Institute of Nanotechnology (Pvt) Ltd. (SLINTEC)
Merger of NANCO (Pvt) Ltd. and SLINTEC (Pvt)
A world class Nanotechnology Laboratory
Establishment of a Nanoscience Park
Medical application of nanoparticles
ex: enhance drug delivery
Some nanoparticles —freely mobile
Negative health and environmental impacts