1. TWO DIMENSIONAL FORM OF
CARBON – GRAPHENE
Supervised By: Submitted By:
Prof. Gursharan Kaur Robin Saini
M.Sc.4th (Sem.) Physics
Roll No. 8057

2. DEPARTMENT OF PHYSICS
KHALSA COLLEGE, AMRITSAR
CERTIFICATE
This is to certify that robin saini has completed assignment on
“TWO DIMENSIONAL FOM OF CARBON – GRAPHENE’’ and has
Submitted to P.G Department of Physics , Khalsa College, Amritsar
Affiliates to Guru Nanak Dev University , Amritsar under my
Supervision .
Prof. Gursharan Kaur
P.G Department of Physics
Khalsa College Amritsar

3.  NANOTECHNOLOGY :- 21st century is the world of research
& technology.
Nanotechnology is one of the newly emerging technology .
which includes the study of manipulating matter on an atomic and
molecular scale. Generally, it deals with materials or structure
possessing atleast one dimension of the size range
1-100 nm
A very Small scale of 10-9 m (1nm) to 10-7 m (100nm) known
as nanoscale and it is used for the measurement of nanotechnology
materials. A nanometer is one billionth of a meter.
THE BASIC DEFINITION :- Nanotechnology is the
engineering of functional system at the molecular scale.

4. RICHARD FEYNMAN’S IDEA OF
NANOTECHNOLOGY:-
The idea of manipulating things atom by atom was
given by Richard Feynman.
He said, “ I want to build a billon tiny factories, models of
each other, which are manufacturing simultaneously ….. The
principles of physics, as for as I can see, do not speak against
the possibility of maneuvering things atom by atom. It is not an
attempt to violate any laws; it is something, in principles, that
can be done; but in practice, it has not been done because we
are too big – Richard Feynman, Nobel prize winner in physics.

5. NANOMATERIALS:- Nanomaterials are the materials which are composed
of one or more nanocomponents. Nanomaterials can be nanoscale in 1 dimension , 2
dimension, 3 dimension. They can exist in single, fused, aggregated form with
spherical, tabular & irregular shapes.
Egs – Nanotubes , buckyball.
TYPES OF NANOMATERIALS
1.Carbon based materials:- These nanomaterials are composed mostly of
carbon, most commonly taking the form of hollow spheres, ellipsoids or tubes.
Spherical or ellipsoidal carbon nanomaterials are referred to as fullerenes, while
cylindrical ones are called nanotubes
2.Metal based materials:- These nanomaterials include quantum
dots, nanogold, nanosilver and metal oxides such as titanium oxides. A quantum dot
is a closely packed semi-conductor

6. 3.Dendrimers: These nanomaterials are nanosized polymers built from
branched units. The surface of a dendrimers has numerous chain ends.
This property could also be for use for catalysis.
4.Composites: Composites combine nanoparticles with other
nanoparticles or with larger bulk type materials.
PROPERTIES OF NANOMATERIALS:
They are hard.
They are ductile.
They are wear resistant.
They are erosion resistant.
They are corrosion resistant.

7. GRAPHENE - TWO DIMENSIONAL FORM OF CARBON
As we studied earlier, Nanomaterials can be 1D,2D and 3D.
In 2D Nanomaterials, we have various examples and one of them is “Graphene”
“Graphene” – a term derives from the Greek word and has a long and interesting
history in many areas of chemistry, physics and engineering.
History/ Discovery of Graphene : In 2004, a group of physicists of Manchester
University, UK, led by Andre Geim and Kostya Novoselov used three-dimensional graphite
for their experiment and extracted a single sheet of graphite and simply stuck a flake of
graphite debris onto plastic adhesive tape, folded the sticky side of the tape over the flake
and then pulled the tape apart cleaving the flake in two. As the process is repeated, the
resulting fragment grew thinner. Once the investigators have many thin fragments, they
examined that pieces and were astonished to find that some were one-atom thick.
Graphene was discovered

8. IMPORTANT POINTS ABOUT GRAPHENE :-
 The term Graphene derived from “Greek word”. It is a monolayer of carbon
atoms that are arranged in plannar and hexagonal form
 Its structure is one – atom thick planar sheets of sp2 - bonded carbon atom
that are densly packed in honey – comb crystal lattice.
 Graphene is optically transparent, chemically inert and an excellent
conductor.
 There is a common belief that 2D crystal cannot exist, graphene, a 2D –
crystal not only exists but it is extremely strong and stiff.
 The cost of graphene with a sample smaller than the thickness of a human
hair is more than 1,000 (as in April 2008).

9. PROPERTIES OF GRAPHENE:
 Graphene has high mobility at room temperature.
 Graphene has a minimum electrical conductivity.
 Graphene is very strong and rigid.
 Graphene sheets are held together by vander walls forces.
 Graphene has high mechanical thermal properties

10. APPLICATIONS
 Transistors: Graphene can be used to make excellent transistors.
Electrons in graphene travel ballistically over sub-micron distances. As a
result, graphene-based transistors can run at higher frequencies and more
efficiently than in silicon transistors
 Gas sensors: Gas molecules that land on graphene affect its electronic
properties in a measurable way. This means that we can create gas sensors
which are sensitive to a single atom or molecule.
 Inert coatings: Graphene is resistant to acids and alkalis such as
ammonia. So it could be used to give objects an atomically thin protective
coating which would provide protection against these agents.
 Molecular sieves: The open honeycomb structure of graphene means
enable atoms and small molecules. It could therefore be used in a way
analogous to a filter paper, trapping large molecule and allowing smaller ones
to pass.

11. FUTURE AHEAD
The study of graphene is "very challenging and fascinating
topic both theoretically and experimentally in condensed
matter physics as well as quantum field theory. Many
physicists are working in this field. Some new results may
come in the 1st half of this 21st century.
THANK YOU