LONDON – The team of scientists has published research showing how light can be used to control the electrical properties of graphene and is claiming the move marks progress in the development of graphene devices.
Graphene, the allotrope of carbon that is a single atom thick of carbon atoms, has unusual electronic properties including high electron mobility. The latest advance is therefore seen as a step towards developing graphene-based electronic devices. Potential applications range from high-speed electronics and solar cells, to highly sensitive chemical sensors.
As a single-layer of sp-2 bonded carbon atoms graphene is the thinnest material known and yet one of the strongest ever tested. It is possible to engineer a super-sensitive sensor because when molecules land on the surface they alter the electrical characteristics in the immediate region.
The team of researchers included scientists from the U.K.'s National Physical Laboratory (NPL), the University of Copenhagen (Denmark), the University of California Berkeley (USA), Chalmers University of Technology (Sweden), Linkoping University (Sweden) and Lancaster University (UK).
In their paper Non-volatile Photo-Chemical Gating of an Epitaxial Graphene-Polymer Heterostructure published in the Journal of Advanced Materials, the team show that when graphene is coated with light-sensitive polymers its electrical properties can be controlled precisely and therefore exploited. At the same time the polymers protect the graphene from contamination.
Light-modified graphene samples have been used by NPL in precision experiments to measure the quantum of electrical resistance. In the future similar polymers could be used to develop robust reliable sensors for smoke, poisonous gases, or any targeted molecule, NPL said.