Quantifying the electron transfer sites of graphene

We demonstrate that graphene modified electrodes do not suffer from thin-layer effects which is commonly observed in carbon nanotube modified electrodes which preclude mechanistic information to be deduced and false claims of electro-catalysis to be inferred. A simple methodology is presented allowing the electron transfer sites of graphene, viz edge plane sites to be readily determined, allowing researchers to make comparisons in the graphene field such as in electrochemical generation and storage devices where graphene has been beneficially applied. Interestingly we find that in comparison of graphene orientated on a surface with that of multi-walled carbon nanotubes, the latter has an identical% of electron transfer sites (edge plane content) with that of the former. (C) 2010 Elsevier B.V. All rights reserved.