Graphene is a single-atom thick sheet of carbon atoms arranged in a honeycomb lattice. It is the strongest material known and has very high electrical and thermal conductivity. Graphene can be produced through mechanical exfoliation of graphite or by heating silicon carbide. Researchers are studying applications of graphene in electronics, energy storage, membranes, and sensors due to its unique properties.

1. Graphene
Boris Torres
MEEN 3344
Material Science

2. Graphene
 Graphene is a one-atom-
thick planar sheet of
carbon atoms that are
densely packed in a
honeycomb crystal lattice.
 Graphite itself consists of
many graphene sheets
stacked together.
 The carbon-carbon bond
length in graphene is
approximately 0.142 nm.

3. Graphene production
 Graphene sheets in solid form
(e.g. density > 1g/cc) is
presently one of the most
expensive materials on Earth.
 Researchers obtained
relatively large graphene
sheets (eventually, up to 100
micrometers in size and visible
through a magnifying glass)
by mechanical exfoliation
(repeated peeling) of 3D
graphite crystals.
 Another method is to heat
silicon carbide to high
temperatures (1100°C) to
reduce it to graphene.

4. Properties of Graphene
 The resistivity of the
graphene sheet is 10^−6
Ω·cm, less than the
resistivity of silver, the
lowest resistivity substance
known at room
temperature.
 Graphene is the strongest
substance known to man.
Its Young's modulus is 0.5
TPa, which differs from
bulk graphite.
 These intrinsic properties
could lead to the possibility
of utilizing Graphene for
NEM systems applications
such as pressure sensors,
and resonators.

5. Properties of Graphene
 Engineering professors at
Columbia University tested
graphene's strength at an
atomic level by indenting a
perfect sample of the
material with a sharp
probe made of diamond.
 Electrons move through
graphene with almost no
resistance, generating little
heat. What's more,
graphene is itself a good
thermal conductor,
allowing heat to dissipate
quickly.

6. Graphene and Applications
 By oxidizing graphene
flakes, and then floating
them in water, the
graphene flakes form a
single sheet and bond very
powerfully called Graphene
oxide paper.
Applications:
 Membranes with controlled
permeability
 Supercapacitors for energy
applications.
 Graphene electronics could
be useful for
communications and
imaging technologies that
require ultrafast
transistors.

7. References
 Graphene http://en.wikipedia.org/wiki/Grapheneaccessed on
March, 29 2009
 Graphene Confirmed the World’s Stronged Known Material
http://gizmodo.com/5026404/graphene-confirmed-as-the-
worlds-strongest-known-material accessed on March, 29 2009
 Nanotechnology Reserchers go Ballistic Over Graphene http://
www.nanowerk.com/spotlight/spotid=2340.php accessed on
March 29, 2009
 TR10: Graphene Transistors
http://www.technologyreview.com/read_article.aspx?
ch=specialsections&sc=emerging08&id=20242 accessed on
March 29, 2009
 Graphene: Charged Up http://www.natureasia.com/asia-
materials/highlight.php?id=77 accessed on March 29, 2009