Graphene and Applications
- (MIT Graphene Roll, MIT)
- Overview
Graphene is a single layer (monolayer) of carbon atoms tightly bound in a hexagonal honeycomb lattice. It is an allotrope of carbon in a planar form of sp2-bonded atoms with a molecular bond length of 0.142 nanometers. Graphene layers stacked on top of each other form graphite with a 0.335 nanometer interplanar spacing. The individual graphene layers in graphite are held together by van der Waals forces, which can be overcome during the exfoliation of graphene from graphite.
Graphene is the thinnest compound known to man, only one atom thick, the lightest material (about 0.77 mg per square meter), and the strongest compound (100-300 times stronger than steel, with a tensile strength of 130 GPa and Young's modulus of 1 TPa - 150,000,000 psi), the best thermal conductor at room temperature (at (4.84±0.44) × 10^3 to (5.30±0.48) × 10^3 W m−1 K−1 ) and is also the best known electrical conductor (studies show electron mobility in excess of 200,000 cm2 V-1 s-1). Other remarkable properties of graphene are its uniform absorption of light in the visible and near-infrared parts of the spectrum (πα ≈ 2.3%), and its potential applicability in spin transport.
With this in mind, one might be surprised to learn that carbon is the second most abundant mass in the human body and the fourth most abundant element (by mass) in the universe, after hydrogen, helium, and oxygen. This makes carbon the chemical basis of all known life on Earth, making graphene potentially an environmentally friendly, sustainable solution for an almost limitless number of applications.
- Unique Properties
Graphene has emerged as one of the most promising nanomaterials because of its
unique combination of exceptional properties: it is not only the thinnest but also one of the strongest materials; it conducts heat better than all other materials; it is an excellent conductor of electricity; it is optically transparent.
Graphene is a two-dimensional nanomaterial with many exceptional properties.
Mechanical properties:
- High tensile strength (130 GPa)
- High Young's modulus (1.02 TPa)
- Large surface area (2630 m2/g)
Electrical properties:
- Excellent conductor of electricity
- Semimetal with unusual electronic properties
Other properties:
- Tough, flexible, and light
- 200 times more resistant than steel
- Five times lighter than aluminum
- Harder than diamonds
- The most conductive material on earth
- Conducts heat better than all other materials
- Optically transparent
Graphene has applications in the energy, construction, health, and electronics sectors.
- Potential Applications
Potential graphene applications include lightweight, thin, flexible, yet incredibly lightweight to, electric/photonics circuits, solar cells, sensing, NEMS, and various medical, chemical and industrial processes enhanced or enabled by the use of new graphene materials.
In 2013, the European Union made a €1 billion grant to be used for research into potential graphene applications. In 2013 the Graphene Flagship consortium formed, including Chalmers University of Technology and seven other European universities and research centers, along with Nokia.
- Biomedicine: Graphene is a material with a single-atom-thick honeycomb structure formed of carbon. It offers unique optical, thermal, electronic and mechanical properties. The material can be made into sheets, flakes, and graphene oxide, offering a variety of applications in the biomedical field. Current research is developing practical applications of graphene for drug delivery, as a material for building biosensors, as a potential antimicrobial agent, and as a scaffold for tissue engineering.
- Flexible Electronics:
- Semiconductors:
- Walter Filtration:
[More to come ...]
