2. TOPICS OF THE DAY
Tools & Technology
i. Carbon Nanotubes
i. Top down
ii. Bottom up
Nanotechnology in India
Possibilities for future
Pitfalls of Nanotechnology
3. NANO & TECHNOLOGY
A Nanometre is a unit of length in the metric
system, equal to one billionth of a metre (10-9).
The words Nano and metre are taken from
Greek; Nano means “Dwarf” and Metre means
“unit of measurement” .
Technology is defined as application of scientific
knowledge for practical purposes, especially in
*Nanometre is roughly the width of 3 or 4 atoms; the
average human hair is about 25000 nanometres
4. DEFINITION OF NANOTECHNOLOGY
Nanotechnology ("nanotech") is manipulation of matter on an
atomic, molecular, and supramolecular* scale.
Nanotechnology refers to constructing and engineering of the
functional systems at a very micro level or we can say at atomic
*Supramolecular chemistry is the domain of chemistry beyond
that of molecules that focuses on the chemical systems made up
of a discrete number of assembled molecular subunits or
The first ever concept was
presented by Dr. Richard Philips
Feynman in 1959.
(Noble Prize in Physics - 1965)
Invention of Scanning Tunneling
Microscope(IBM) in 1981 and discovery
of Fullerence*(C 60) (Rice and Sussex
Univ.) in 1985 led to Emergence of
The term Nano-technology was
coined by Japanese Professor Dr. Norio Taniguchi in 1974.
*A fullerene is a molecule of carbon in the form of a hollow
sphere, ellipsoid, tube, and many other shapes.
6. “Engines of Creation” first
book on Nanotechnology by
K Eric Dexler and invention of
“Atomic Force Microscope” in
IBM logo made with individual
atoms in 1989.
Discovery of Carbon Nanotubes
by S. Iijima in 1991.
First book on nanomedicine named “Nanomedicine”
by R. Freitas in 1999.
7. The early 2000s also saw
the beginning of commercial
applications of nanotechnology,
although these were limited to
bulk applications of nanomaterials.
Silver nano platforms for using
silver nano particles as an anti
bacterial agent, nano particle
based transparent sunscreens,
and carbon nanotubes for stain
11. TOOLS AND TECHNOLOGY
Development of Atomic Force Microscope and
Scanning Tunneling Microscope helped in
proving theories of nanotechnology.
This also helped in development of
nanolithographic* techniques such as
i. Optical Lithography
ii. X Ray Lithography
iii. Electron Beam Lithography(Ink Jet Printers)
*Nanolithography is the branch of nanotechnology
concerned with the study and application of
fabricating nanometer-scale structures, meaning
patterns with at least one lateral dimension between 1
and 1,000 nm.
12. CARBON NANOTUBE
Carbon nanotubes (CNTs) are allotropes
of carbon with a cylindrical nanostructure.
These cylindrical carbon molecules have
unusual properties, which are valuable for
nanotechnology, electronics, optics and
other fields of materials science and
technology. Owing to the material's
exceptional strength and stiffness,
nanotubes have been constructed with
length-to-diameter ratio of up to
132,000,000:1, significantly larger than for
any other material.
In addition, owing to their extraordinary
thermal conductivity, mechanical, and
electrical properties, carbon nanotubes find
applications as additives to various
structural materials. For instance,
nanotubes form a tiny portion of the
material(s) in some (primarily carbon fiber)
baseball bats, golf clubs, car parts or
13. APPLICATIONS OF CARBON NANOTUBES
i. Bicycle components.
ii. Structures of Aircrafts.
iv. Tips/Sensors of Atomic Force Microscopes.
Nanorods are one morphology of nanoscale
objects. Each of their dimensions range from 1–100
nm. They may be synthesized from metals or
semiconducting materials. Standard aspect ratios
(length divided by width) are 3-5. Nanorods are
produced by direct chemical synthesis. A
combination of ligands* act as shape control agents
and bond to different facets of the nanorod with
different strengths. This allows different faces of the
nanorod to grow at different rates, producing an
*a ligand is an ion or molecule that binds to a central
metal atom to form a coordination complex.
15. USES OF NANORODS
One potential application of nanorods is in display
technologies, because the reflectivity of the rods can be
changed by changing their orientation with an applied
electric field. Another application is for
microelectromechanical systems (MEMS). Nanorods,
along with other noble metal nanoparticles, also function
as theragnostic agents. Nanorods absorb in the near IR,
and generate heat when excited with IR light. This
property has led to the use of nanorods as cancer
therapeutics. Nanorods can be conjugated with tumor
targeting motifs and ingested. When a patient is
exposed to IR light (which passes through body tissue),
nanorods selectively taken up by tumor cells are locally
heated, destroying only the cancerous tissue while
leaving healthy cells intact
Nanorobotics is an emerging technology
field creating machines or robots whose
components are at or near the scale of a
nanometre. More specifically, nanorobotics
(as opposed to microrobotics) refers to the
nanotechnology engineering discipline of
designing and building nanorobots, with
devices ranging in size from 0.1–10
micrometres and constructed of nanoscale or
molecular components. The terms nanobot,
nanoid, nanite, nanomachine, or nanomite
have also been used to describe such devices
currently under research and development.
18. NANOTECHNOLOGY APPROACH
There are two approaches for synthesis
of nano materials and the fabrication of
Top down approach refers to slicing or
successive cutting of a bulk material to
get nano sized particle.
Bottom up approach refers to the build
up of a material from the bottom: atom
by atom, molecule by molecule or
cluster by cluster.
19. Both approaches play very important role in modern
industry and most likely in nano technology as well.
There are advantages and disadvantages in both
Attrition or Milling is a typical top down method in
making nano particles, where as the colloidal dispersion
is a good example of bottom up approach in the
synthesis of nano particles.
The biggest problem with top down approach is the
imperfection of surface structure and significant
crystallographic damage to the processed patterns.
These imperfections which in turn leads to extra
challenges in the device design and fabrication. But this
approach leads to the bulk production of nano material.
Regardless of the defects produced by top down
approach, they will continue to play an important role in
the synthesis of nano structures.
20. Though the bottom up approach often referred in
nanotechnology, it is not a newer concept. All the living
beings in nature observe growth by this approach only and
also it has been in industrial use for over a century.
Examples include the production of salt and nitrate in
Although the bottom up approach is nothing new, it plays an
important role in the fabrication and processing of nano
structures. There are several reasons for this and explained
When structures fall into a nanometer scale, there is a little
chance for top down approach. All the tools we have
possessed are too big to deal with such tiny subjects.
Bottom up approach also promises a better chance to obtain
nano structures with less defects, more homogeneous
On the contrary, top down approach most likely introduces
internal stress, in addition to surface defects and
33. NANOTECHNOLOGY IN INDIA
Ministry of Electronics and Information Technology
has taken a lead to promote Nanotechnology in
Dept. of Electronics and Information
Technology (DeitY) has initiated Indian
Nanoelectronics User Programme (INUP)
and established Centres of Excellence in
Nanoelectronics in IISc and IIT-B.
About 400 researchers are being imparted
hands on training in Nanofabrication at
these centres every year.
34. Following are the thrust areas identified by the
Working Group of Nanotechnology:
i. Post Moore Electronics beyond 10 nm
ii. Sensors (health, agriculture, security etc.)
iii. Organic Electronics
iv. Computational Nanoelectronics
v. Setting up prototyping and incubation
facilities for a range of devices/products
The efforts have paid off well. India published over
23000 papers in nanoscience in the past 5 years. In
2013, India ranked third in the number of papers
published, behind only China and USA.
There have been 300 patent applications in the
Indian Patent Office in 2013, ten times that of 2006.
35. The amount India spends on nanotechnology
research is still just a fraction of the research
spending of countries like Japan, USA, France and
Only 16 papers from India appeared in the top 1% of
the publications in 2011. Also, the number of patents
applied from India to the US patent office
contributes to only 0.2% of the total applications.
Though people look at nanoscience and technology
very positively, the number of students following
undergraduate and graduate degrees in the area is
low and career prospects still extremely limited. The
number of PhDs awarded in nanoscience and
technology is about 150 per year; a very small
number compared to the target of producing 10,000
PhD students annually over the next decade
articulated by the Ministry of Human Resource
36. PITFALLS OF NANOTECHNOLOGY
Nanoparticles can get into the body through the skin , lungs
and digestive system, thus creating free radicals that can
cause cell damage.
Once the nanoparticles are in the bloodstream, they can cross
the blood-brain barrier.
The most dangerous applications of nanoparticles is in the
military, where Nano Bombs that contain deadly virusus
which are engineered to replicate themselves can wipe out a
community, country or an entire civilisation.
Nanobots because of their self replicating behaviour may lead
to Grey Goo*
*Grey goo is a hypothetical end of the world scenario involving
molecular nanotechnology in which out-of-control self-
replicating robots consume all biomass on Earth while building
more of themselves, a scenario that has been called
ecophagy ("eating the environment", more literally "eating the