Radio-frequency plasma assisted reduction and nitrogen doping of graphene oxide

The plasma treatment of graphene oxide (GO) is a promising method for safely carrying out the surface modification of GO because the treatment can be performed at room temperature without the use of toxic processing gases. In this study, plasma reduction and nitrogen doping were carried out on GO, and the chemical property of the treated GO were investigated in detail, thereby demonstrating the superior properties of plasma treatment. Unlike thermal reduction, in which epoxide and hydroxyl groups were preferentially removed, plasma reduction removes all types of functional groups, thus realizing a novel form of modified GO surface. Since the functional groups might behave as an active site for doping, its relative abundance during the nitrogen plasma treatment of GO at room temperature resulted in a large amount of the nitrogen content (up to 19.1 at%). These characteristics of plasma-assisted GO treatment are expected to improve the device performance and can open up new possibilities for GO applications.