Updated: Nov 6, 2019
Graphene is one of the varieties of carbon. It is one of the first discovered and stable two-dimensional materials. Graphene consists of a single, transparent layer, tightly packed atoms. Its structure resembles a honeycomb.
Other varieties of carbon are diamond or graphite.
The lattice consists of many layers of graphene stacked on top of each other. Already in the nineteenth century, scientists speculated that graphite consists of layers.
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However, it was only at the beginning of the 20th century that this was proven by scientific research. In 1947, the first theoretical description of graphene was created, but its proper discovery and physical separation from graphite occurred almost 40 years later.
Andre Geim and Konstantin Novoselov from the University of Manchester rediscovered graphene in 2004 by pulling graphene layers from graphite and transferred them onto thin SiO2 on a silicon wafer in a process called either micromechanical cleavage or the Scotch tape technique. In 2010, they received the Nobel Prize in Physics for their discovery. It is currently the thinnest, lightest and strongest material known to man.
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It also conducts electricity and heat very well and is very flexible. Graphene can easily be extended by up to 20%. Scientists recognize that the new material is 100 times stronger than the strongest steel in the world although it consists of only one layer of carbon atoms.
The graphene membrane is impervious to gases, including helium atoms, and as a result of simple processing, the material can change from a perfect conductor to a perfect insulator. In a future perspective, graphene based photovoltaic cells could be used in i.e. clothing; to help recharge your mobile phone, or even used as retro-fitted photovoltaic window screens or curtains to help power your home.