Graphene: unexpected science in a pencil line
An artist’s impression of a rippled graphene sheet showing the “chicken wire” arrangement of the carbon atoms.
Graphene is the thinnest material known and was only isolated in 2004 by a group of physicists from Manchester led by Andre Geim FRS and Kostya Novoselov, who actively explored its properties. This work proved so pioneering that they were awarded the 2010 Nobel Prize for Physics.
Graphene is a single atom thick, two dimensional film of Carbon atoms arranged in a “chicken wire” like structure, which was previously thought to be unstable in its free form. It is very strong, transparent and highly conductive with potential applications from strengthening aircraft wings to making mobile phone touch screens and faster computers.
How does it work?
Dr Leonid Ponomarenko showing a graphene nanodot transistor.
Graphene was originally made by using sticky tape to peel it from graphite (as found in a pencil lead). Many of its properties are unique or far superior to those in other materials, which make it such an exciting new material to study. The electric current in graphene is carried by charge carriers which appear to have no mass and can travel large distances without scattering. This makes it a good testing ground for interesting quantum effects and gives it many applications for fast electronics.
It is extremely transparent and being such a good electrical conductor makes it an ideal transparent electrode in LCD displays and solar cells. Scientists have also made gas sensors from graphene which are much smaller than a hair’s width and so sensitive they can detect when a single gas molecule is present on them. It makes an extremely strong support membrane for observing biological molecules in a Transmission Electron Microscope and is so electron transparent even individual metal atoms can be seen on its surface. It is the strongest material found so far, which can be used to make ultra-strong, conductive composite materials.
Click here to listen to an audio interview with this exhibit.