Graphene Oxide: Preparation, Functionalization, and Electrochemical Applications

Graphene, which consists of a one-atom-thick planar sheet comprising an sp-bonded carbon structure with exceptionally high crystal and electronic quality, is a novel material that has emerged as a rapidly rising star in the field of material science. Facile electron transfer between graphene and redox species opens up opportunities for sensing strategies based on direct electron transfer rather than mediation. It is not surprising, therefore, that graphene has recently attracted great attention worldwide from the electrochemical community. Despite its short history, this 2D material has already revealed potential applications in electrochemistry, and remarkably rapid progress in this area has already been made. The oxygen functional groups have been identified as mostly in the form of hydroxyl and epoxy groups on the basal plane, with smaller amounts of carboxy, carbonyl, phenol, lactone, and quinone at the sheet edges.