With all sources of minerals and ores desiccating up, there is urgent need of deriving a new replacement compound. The future of our industries could hinge on a single material – and our industries are currently buzzing over the potential of graphene. It is the strongest, slimmest and most malleable material in existence.
Graphene emerged from the carbon family, its allotrope are graphite and diamond. People sometimes use the word graphene in place of ‘carbon nanotubes. Sheets of graphene roll up into nano-scale tubes, forming CNTs (just like a micro-straw). The walls have the thickness of single atom, but the tube is stable and less reactive with other substances than regular, linear graphene.
What exactly is Graphene?
Graphene is an allotrope of carbon having honeycomb sheets of carbon, with the thickness lying at just about one atom. The structure too, is symmetrical to graphite. It consists of a pattern called the crystal lattice – consisting of atoms arranged in a regular repeating, 3D structure. Invisible bonds between the atoms that hold them together. Other allotropes like diamond and graphite too have a 3D structure.
Atoms tightly bond in 3D tetrahedrons in diamond. This gives diamond its hardness. In graphite, atoms tightly bond in 2D layers, and relatively weak forces hold the layers above and below together. The remarkable thing about graphene is that its crystalline structure is two-dimensional. In other words, it has a close resemblance to the graphite structure (hexagonal rings), giving a honeycomb-like appearance. But the distance between the two layers is an one atom long. To produce a 1 mm thick graphene, one needs 3 million such layers.
Unlike other allotropes of carbon, graphene acts as a conductor. Some scientist even call it a semi-metal, owing to its absence of a band-gap in its atomic structure.
What is the band-gap?
The gap between the energy of an electron when it binds to an atom and the conduction band, where it moves freely, defines a band gap. An electron cannot exist in an energy level between those two states. Photovoltaic cells could find its best application. Manufacturers currently widely use silicon in the production of photovoltaic cells. But it may be face competition from graphene. As silicon turns light into electricity, it produces a photon for every electron produced. A decent amount of energy wastes. This isn’t the case with graphene. Graphene also works on multiple wavelengths, making it beneficial and efficient.
Graphite is not Graphene
Graphite
This is a naturally-occurring form of crystalline carbon. Scientists find this mineral in metamorphic and igneous rocks, where it shares a similar hexagonal arrangement. It is an extremely soft, cleaves with very light pressure and comprises of a very low specific gravity. It contemporarily it acts as an insulator to heat and is nearly inert in contact with almost any other material.
Graphene
In labs, scientists synthetically make graphene, which is fundamentally one single layer of graphite. Comprises of formation of a layer of sp2 bonded carbon atoms, arranged in a honeycomb (hexagonal) lattice. The scientists have also recorded it as the strongest material ever, with 100 times more strength than structural steel. The Chemical Vapor Deposition (CVD) can synthesize it.
Properties of Graphene
• It is a micro material that sp2 hybridizes. This is actually the reason for its magical applications and super-strength.
• Scientists say that the strength of its 0.142 nm-long carbon bonds makes it the strongest material discovered. It consists of an ultimate tensile strength of 130 Gigapascals, compared to 400 Gigapascals for A36 (structural) steel, or 375 Gigapascals for Kevlar. Not only is graphene extraordinarily strong, it is also very light at 0.77 milligrams per square meter.
• This is a perfect material but isn’t naturally occurring. People need to develop it synthetically, and it is an expensive affair.
What can we do with graphene?
• This is likely to be used in the manufacturing of supercapacitors, to store large amounts of electricity. Graphene-based micro-supercapacitors will likely be developed for use in low energy applications such as smartphones and portable computing devices and could potentially be commercially available within coming years.
• In aircraft, it is a substitute for the carbon-fibre as it is very light and strong. It can replace steel structures in aircrafts, reducing the weight and improving efficiency.
The pores are extremely small and less brittle than the aluminum oxide. So it could be used in desalination systems and for biofuel extraction and creation.
