New material

The university research team that discovered graphene has now introduced graphane, a novel two-dimensional material that may give scientists additional control of graphene’s electronic properties.

Graphene, which was discovered at Manchester University in 2004, is a one-atom-thick crystal with highly conductive properties. Future applications for the material are said to include electronics and photonics.

Research published today by Prof Andre Geim and Dr Kostya Novoselov, who led the group that discovered graphene in 2004, suggests its uses could be far greater.

The scientists, from the University’s School of Physics and Astronomy, have used hydrogen to modify graphene into graphane.

The addition of a hydrogen atom on each of the carbon atoms in graphene achieved the new material without altering or damaging its one-atom-thick structure. The new material is said to have excellent insulating properties, unlike graphene which is a good conductor.

‘Graphene is an excellent conductor and is tipped for many electronic applications,’ said Dr Novoselov. ‘However it was tempting to look at ways to gain additional control of its electronic properties through the use of chemistry.

‘Our work proves that this is a viable route and hopefully will open the floodgates for other graphene-based chemical derivatives. This should widen the possible applications dramatically.’

The electronic properties of graphene have already led researchers to look at ways the material could be used in the development of increasingly small and fast transistors. However, the absence of the energy gap in the electronic spectra forced scientists to use rather complex graphene-based structures such as quantum point contacts and quantum dots for this purpose.

The discovery that graphene can be modified into new materials, fine tuning its electronic properties, has opened up possibilities in the development of future electronic devices from this material.

Prof Geim said: ‘The modern semiconductor industry makes use of the whole period table: from insulators to semiconductors to metals.

‘But what if a single material is modified so that it covers the entire spectrum needed for electronic applications?

‘Imagine a graphene wafer with all interconnects made from highly conductive, pristine graphene whereas other parts are modified chemically to become semiconductors and work as transistors.’