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GRAPHENE AN
INTRODUCTION TO THE
FUNDAMENTALS
PRESENTED BY :
SAIYED MOH. MARUF (D19ME112)
MENTOR : MR. RUGNESH PATEL
ME-349 SUMMER INTERNSHIP -1
15 APRIL 2020 TO 31 MAY 2020
What is Graphene ?
 Graphene is a flat monolayer of carbon atoms tightly packed into a
two- dimensional (2D)honeycomb structure ,which works on
diffraction of electrons.
 It is a single layer of Graphite (pure crystalline carbon)
 Graphite was discovered in 1564 at Sea Thwaite (Borrowdale),
Northumberland
 ‘Graphene’ was first isolated in the lab by Professor Andre Gem with
former student Konstantin Novoselov at the University of
Manchester, England in 2004
 2010 Nobel Prize for “groundbreaking experiments regarding the
two-dimensional material graphene” (Both were later Knighted,
twice)
 Carbon-the basis of all known life on the earth-has surprised the
scientific community once again with its exotic properties.
Introduction
 Graphene can be described as
a one atom thick layer of
graphite.
 A layer of atoms arranged in a
honeycomb structure.( it
forms a sheet by arranging in
this type of format and the
thickness of sheet is
measured which is 1 atom
thick)
 It would take 3 million stacked
sheets of it to equal the width
of a pencil tip.
Introduction
 Despite being the lightest known material It’s also the
strongest
 Harder than diamond and to get a idea here is a
comparison with steel
 And 200x stronger than steel
 It conducts electricity and heat better than any other
material it is steel not being found how much but it more
(more than silver but how much more not being conclude)
accurate so we don’t know the perfect measure of electric
conductivity
 It is so dense as it is in honey comb structure so it can only
pass the water through it not anything else , hence it can be
use for water purification in near by future
 Graphene has proven to be an anti-corrosion coating for
metal that is transparent, thinner, and longer lasting than
anything that currently exists.
History
 One of the very first patents pertaining to
the production of Graphene was filed in
October, 2002 entitled, “Nano- scaled
Graphene Plates”.
 Two years later, in 2004 Andre Geim and
Kostya Novoselov at University of
Manchester extracted single-atom-thick
crystallites from bulk Graphite
 Geim and Novoselov received several
awards for their pioneering research on
graphene, notably the 2010 Nobel Prize In
Physics.
Structure

Graphene is a 2-dimensional network of carbon atoms.

By stacking of these layers on top of each other, the
well known 3-dimensional graphite crystal is formed.

It is a basic building block for graphitic materials of all
other dimensionalities.

It can be wrapped up into 0D fullerenes, rolled into 1D
nanotubes or stacked into 3D graphite.

Sheets of graphene are bonded by loose bond in
graphite. These bonds are broken and sheets are
isolated to form graphene. These isolated hexagonal
sheets are graphene.
Structure
Mechanical Properties
 To calculate the strength of
graphene, scientists used a
technique called Atomic Force
Microscopy.
 It was found that graphene is
harder than diaomnd and 200
times harder then steel.
 The tensile strength of graphene
exceeds 1 Tpa.
 It is stretchable up to 20% of its
initial length
 It is expected that graphene’s
mechanical properties will find
application into making a new
generation of super strong
composite material and along
combined with its optical
properties, making flexible
displays.
Chemical Properties
 Graphene is chemically the most reactive form of carbon.
 Only form of carbon (and generally all solid materials) in which each
single atom is in exposure for chemical reaction from two sides (due to
the 2D structure).
 Carbon atoms at the edge of graphene sheets have special chemical
reactivity.
 graphene burns at very low temperature (e.g., 350 °C).
 Graphene has the highest ratio of edgy carbons (in comparison with
similar materials such as carbon nanotubes).
 Graphene is commonly modified with oxygen- and nitrogen- containing
functional groups
Electronic Properties





It is a zero-overlap semimetal (with both holes and
electrons as charge carriers) with very high electrical
conductivity.
Electrons are able to flow through graphene more easily
than through even copper.
The electrons travel through the graphene sheet as if they
carry no mass, as fast as just one hundredth that of the
speed of light.
High charge carrier mobility, for which values of 10,000
cm²/Ns, in some cases even 200,000 cm²/Ns were
reported.
Best Known conductor till now.
In an insuator or semiconductor, an electron bound to an atom can break free only if it gets enough
energy from heat or passing photon to jump the ‘band gap’. But in graphene the gap is infinitesimal.
This is the main reason why graphene’s electron can move easily and very fast.
Thermal Properties




Graphene is a perfect thermal conductor
Its thermal conductivity is much higher than all the other carbon
structures as carbon nanotubes, graphite and diamond (> 5000
W/m/K) at room temperature
Graphite, the 3 D version of graphene, shows a thermal conductivity
about 5 times smaller (1000 W/m/K)
The ballistic thermal conductance of graphene is isotropic, i.e. same
in all directions
 The material's high electron
mobility and high thermal
conductivity could lead to chips
that are not only faster but also
better at dissipating heat.
 This schematic shows a threedimensional stacked chip with
layers of graphene acting as heat
spreaders.
Some Other Properties









Thinnest imaginable and strongest material ever measured
Stiffest known material (stiffer than diamond)
Most stretchable crystal (up to 20% elastically)
Record thermal conductivity (outperforming diamond)
Highest current density at room T (million times of those in
copper)
Highest intrinsic mobility (100 times more than in Si)
Conducts electricity in the limit of no electrons
Good for flexible, wearable devices
It is transparent: One atom-thick layer sheet absorbs ~2.3%
visible light (πα).
What makes Graphene Different from
other ?






Unique structure.
All in one Properties
Low cost
Abundant element
Chemically inert
Thermal stability
Integrated Circuits
 Graphene has a high carrier
mobility, as well as low noise,
allowing it to be used the
channel in a field-effect as
transistor.
 Processors using 100 GHz
transistors on 2-inch (51 mm)
graphene sheets.
 Graphene-based integrated
circuit handled frequencies up
to 10 GHz.
 Transistors printed on flexible
plastic that operate at 25
gigahertz.
 Terahertz-speed transistor
Optical Electronics
 Graphene's high electrical
conductivity and high optical
transparency make it a
candidate for transparent
conducting electrodes.
 Graphene's mechanical
strength and flexibility are adva
ntageous compared to indium
tin oxide, which is brittle.
 So it would work very well in
optoelectronic touchscreens,
liquid crystal displays,
applications: organic
photovoltaic cells, and organic
light-emitting diodes.
Solar Cells
 Graphene turned to be a
promising material for
photoelectrochemical energy
conversion in dye sensitized
solar cells.
 The transparent, conductive,
and ultrathin graphene films
are fabricated from exfoliated
graphite oxide, followed by
thermal reduction.
 The obtained films exhibit a
high conductivity of 550 S/cm
and a transparency of more
than 70% over 1000-3000 nm.
Electronics Engineering
Will definitely replace silicon
and germanium as device
material.
Conducting material on PCBS.
Single molecule sensors Touchscreens
Graphene transistor. Graphene
integrated circuits. Graphene
chips.
Applications
 While as of 2014, graphene is not used in commercial applications,
many have been proposed and/or are under active development, in
areas including electronics, biological engineering, filtration,
lightweight/strong composite materials, photovoltaics and energy
storage.
 Graphene makes experiments possible that give new twists to the
phenomena in quantum physics.
 Applications in electrical engineering.
 Mechanical engineering.
 Most important in electronics engineering as component material.
 As a superconducting material. Micro electronics.
 Transparent conducting electrode.
 Solar cells
 Graphene bio devices.
Graphene in Advanced Mobile
Technology
 Flexibility and Slim
 Graphene phones are very easily
placed in the pocket
 Graphene phones are slimmer as
compared to the smart phones.
 Graphene phones are thinner like
floppy disc.
 Graphene phones can be also wore
as wristwatches.
 Graphene phones as cannot be broken down as it is
a metal.
 Both the graphene (carbon) and the silicon flex with
the battery's charge cycles, but don't break.
 Thus the graphene phones are charged quickly and
can remain charge for a longer time
 Large memory capacity
 Ultra-low power consumption
 Compatible with state-of-the-art technology
 Strong immunity to short channel effects
Future
 In future the mobile technology
would be completely dependent
on the graphene.
 The phones would be connected
on the laptop and computer
without any device & then the
work can be done on the laptop
 It’s a Wonder Material that could
revolutionize the world
References
 Graphene an introduction to the fundamentals and industrial
application by Madhuri Sharon, Maheshwar Sharon, Ashutosh
Tiwari
 https://en.m.wikipedia.org/wiki/Graphene
 Applications of Graphene and Graphene-Oxide Based
Nanomaterials by Sekhar Chandra Ray
 Functionalization of Graphene by Vasilios Georgakilas
 Graphene Nanomaterials Fabrication, Properties and
Applications by Satyendra Mishra and Dharmesh Hansora
 Graphene Technology by Soroush Nazarpour and Stephen R.
Waite
 https://www.researchgate.net/publication/300223835_Literatu
re_Review_and_Research_Background
 https://graphene-flagship.eu/material/Pages/The-history-ofgraphene.aspx
 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6304494/
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