Graphene electrodes key to burgeoning electronic field

An international team of researchers have found a new way to tune the functionality of next-generation electronic devices – using graphene electrodes.

This discovery will allow the development of smaller, higher-performance devices for use in a range of applications such as energy conversion and storage, flexible electronics and molecular sensing. It will aid the growing field of molecular electronics – nanotechnology that uses molecules as electrical components.

This field is currently hindered by the lack of stable contacts between molecules and metals that can operate at room temperature and produce repeatable results. In addition to mechanical stability, graphene also has very high electronic and thermal conductive properties – making it an attractive proposition for molecular electronics.

Dr Ivan Rungger, from the National Physical Laboratory and co-author of the study in Science Advances said: "We find that by carefully designing the chemical contact of molecules to graphene-based materials, we can tune their functionality.”

The researchers studied current flowing through molecules attached to graphite or multi-layered graphene electrodes using an experimental technique to measure molecule-to-molecule variations. Combined with theoretical calculations, they concluded that the nature of the chemical contact of a molecule to the top graphene layer dictates the functionality of single-molecule electronic devices.

Dr Veerabhadrarao Kaliginedi, from the University of Bern and co-author, said: “We are confident that our findings represent a significant step towards the practical exploitation of molecular electronic devices, and we expect a significant change in the research field direction following our path of room-temperature stable chemical bonding.”