Graphene is a two-dimensional allotrope of carbon, discovered in 2004 by Andre Geim and Konstantin Novoselov. It is an extremely strong material with unique electrical and thermal properties. Due to its strength, flexibility and impermeability, graphene has potential applications in many fields including electronics, energy storage, and sensors.
Graphene was first isolated as a single layer of carbon atoms by peeling off a piece of Scotch tape from a block of graphite. This method, known as the “Scotch tape” technique, can also be used to create other two-dimensional materials such as MoS2 and h-BN. Graphene can also be produced using chemical vapor deposition (CVD), where methane gas is decomposed on a metal catalyst at high temperatures to form a thin film of graphene.
The structure of graphene consists of carbon atoms bonded together in a honeycomb lattice. Each atom is bonded to three others via sp^2 hybrid orbitals, forming strong covalent bonds. The resulting sheet is just one atom thick but very strong – about 200 times stronger than steel! Graphene also has unique electronic properties due to its honeycomb structure. The pi orbitals formed by the sp^2 hybridization are delocalized over the entire sheet, giving rise to special electronic band structure that allows electrons to flow freely through the material without resistance – making it an excellent conductor of electricity.
Graphene’s exceptional properties have led to many potential applications in various fields. In electronics, for example, graphene could be used as transparent electrodes or interconnects in displays and solar cells or as ultrafast transistors for next-generation computer chips; while in energy storage devices such as batteries or supercapacitors, graphene could improve charge/discharge rates and specific capacitance values. Additionally, because it is impermeable even to helium atoms, graphene could be used for developing new types of flexible water desalination membranes or safer nuclear reactors with improved containment vessels . Moreover , being an excellent conductor of heat , graphene holds promise for use in thermal management applications such as cooling computer chips . Finally , due to its unique optical absorption properties , scientists are investigating if graphene can be used for developing novel optoelectronic devices such as photodetectors or light sources .