1. Jared Johnson & Jason Peltier
Graphene
Graphene physically acts as a 2-Dimensional material. This leads to many properties that are electrially beneficial, such as high electron moblity and lowered power usage. Graphene is currently in its infant stages and is undergoing many applications and studies.
Jared Johnson & Jason Peltier
April 30th

2. Introduction What is Graphene Discovery Electrical Properties
Mechanical Strength
Optical Properties
Applications
Devices

3. What is Graphene 2-dimensional, crystalline allotrope of carbon
Allotrope: property of chemical elements to exist in two or more forms
Single layer of graphite
Honeycomb (hexagonal) lattice

4. Graphene vs Other Allotropes
Graphene - Top Left
Graphite - Top Right
Nanotube - Bottom Left
Fullerene - Bottom Right

5. Discovery Studies on graphite layers for past hundred years
Graphene theory first explored by P.R. Wallce (1947)
Andre Geim & Kontantin Novoselov Nobel Peace Prize (2010)
Physics observed using TEM

6. Electronic Structure First Brillouin Zone (red)
Second Brillouin Zone (yellow)
Six corners of first Brillouin zone called Dirac points (also called K points)
Electrons and holes called Dirac fermions

7. Electronic Structure
Dirac Points are the transition between the valence band and the conduction band
The six Dirac points can be divided into to two in-equivalent sets of three (K and K'), represented by the black and white dots on part (a)
The points within each set are all equivalent because they can reach each other by reciprocal lattice vectors
Part (b) shows that the dispersion relation close to the K points looks like the energy spectrum of massless Dirac particles

8. Electrical Properties
The Fermi level can be changed by doping to create a material that is better at conducting electricity
Experimental graphene's electron mobility is 15,000 cm2/(V*s) and theoretically potential limits of 200,000 cm2/(V*s)
Graphene electrons are like photons in mobility due to lack of effective electron and hole mass
These charge carriers are able to travel sub-micrometer distances without scattering

9. Mechanical Strengths Bond length is .142 nm long = very strong bond
Strongest material ever discovered
ultimate tensile strength of 130 gigapascals compared to 400 megapascals for structural steel
Very light at 0.77 milligrams per square metre, paper is 1000 times heavier
Single sheet of graphene can cover a whole football field while weighing under 1 gram
Also, graphene is very flexible, yet brittle (preventing structural use)

10. Photograph of graphene in transmitted light.
Optical Properties
Absorbs 2.3% white light
Optical electronics absorb <10% white light
Highly conductive
Strong and flexible
Photograph of graphene in transmitted light.

11. Other Applications OLED Techonologies Body Armour
Lightweight Aircraft/vehicles
Photovoltaics
Superconductor/battery
Filtration

12. Devices

13. Summary & Conclusion
Graphene, a singular layer of graphite, has been discovered to have unique properties. The high mobility and ability to travel short distances without scattering makes it one of the best materials for electrical applications. Graphene's mechanical and optical properties also allow its use to go beyond electrical applications.

14. References
"Allotrope." Wikipedia. Wikimedia Foundation, 16 Apr Web. 17 Apr <
Cooper, Daniel R. "Experimental Review of Graphene." Hindawi Publishing Corporation, 3 Nov Web. 16 Apr <
De La Fuente, Jesus. "Graphene." Graphenea. Web. 26 Apr <
Geim, Andre. "Nobel Lecture." Nobel Prize, 8 Dec Web. 18 Apr <
"Graphene." Wikipedia. Wikimedia Foundation, 16 Apr Web. 17 Apr <
Neamen, Donald A. Semiconductor Physics and Devices: Basic Principles. New York, NY: McGraw-Hill, Print.
Roos, Michael. "Intermolecular vs Molecule–substrate Interactions." Beilstein Journal of Nanotechnology , Web. 15 Apr < journals.org/bjnano/single/articleFullText.htm?publicId= >.
"Graphene." NUS Graphene Research Centre. National University of Singapore, n.d. Web. 28 Apr <

15. Last Slide
Graphite had been studied for over a hundred years but Geim and Novoselov found how to isolate it to be graphene and some applications for its use
The reason graphene is such a beneficial material is due to its 2D like nature and short/strong bonds
It has a super high conductivity and an electron mobility of ,000 cm2/(V*s)
It is the strongest material ever discovered, however its brittle nature cannot be used structurally (only to help reinforce)
One of the most common current uses of graphene is in OLEDs