As the field of nanotechnology is in fast progress, we discover many revolutionary substances, and their ever-widening uses which take many by astonishment. One such wonder-nanomaterial is graphene. So let's see what actually is graphene
Graphene is a substance made of pure carbon, with atoms arranged in a regular hexagonal pattern similar to graphite, but in a one-atom thick sheet. It is a very light substance, with a 1 square meter sheet weighing only 0.7 milligrams. It is an allotrope of carbon. The term graphene was coined as a combination of graphite and the suffix -ene by Hanns-Peter Boehm, who described single-layer carbon foils in 1962. Graphene is most easily visualized as an atomic-scale chicken wire made of carbon atoms and their bonds. The carbon-carbon bond length in graphene is about 0.142 nanometers. It is stronger than diamond and conducts electricity 100 times faster than the silicon in computer chips.
In essence, graphene is an isolated atomic plane of graphite. From this perspective, graphene has been known since the invention of X-ray crystallography. It is now well known that tiny fragments of graphene sheets are produced whenever graphite is scratched. In 2008, graphene produced by exfoliation was one of the most expensive materials on Earth. One of the methods of obtaining graphene is by heating silicon carbide (SiC) to high temperatures (>1100 °C) to reduce it to graphene.
Graphene differs from most conventional three-dimensional materials. Intrinsic graphene is a semi-metal or zero-gap semiconductor. Understanding the electronic structure of graphene is the starting point for finding the band structure of graphite.
Researchers have found that adding graphene to epoxy composites may result in stronger/stiffer components than epoxy composites using a similar weight of carbon nanotubes. Graphene appears to bond better to the polymers in the epoxy, allowing a more effective coupling of the graphene into the structure of the composite.
Researchers have built a solar cell that uses graphene as a electrode while using buckyballs and carbon nanotubes to absorb light and generate electrons. Researchers have also found that graphene can replace indium-based electrodes in organic light emitting diodes (OLED). These diodes are used in electronic device display screens which require low power consumption.
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