Graphene modification based on plasma technologies

Abstract

Plasma contains highly reactive species, including electrons, ions, radicals, photons, etc., which are critical for catalyzing or directly participating in chemical reactions. Plasma is a highly efficient tool in chemical synthesis and material modification, since it can make the chemical reactions that are difficult or even impossible to occur under thermal equilibrium conditions take place and accelerate through its catalysis. The chemical reactivity of graphene under conventional conditions is low, which means that the reaction of graphene requires high temperature, high pressure and/or strong acid or alkali, thereby restricting the synthesis and modification of novel graphene-derived materials. Plasma-assisted graphene reaction can trigger a series of chemical reactions, such as reduction, oxidation, defect repair, doping, grafting, epitaxial growth and cross-linking of graphene, under ambient temperature and pressure without any corrosive conditions. It provides great potentials for the functional modification of graphene and the synthesis of graphene composites, which deserve further exploration. Over the past decade, a number of studies of graphene synthesis and modification by using plasma with distinctive characteristics have been reported. However, most of reports focused on the presentation of technical routes and corresponding results, and the research on chemical reaction kinetics is still far from being fully addressed. In this review, we make a comprehensive discussion about these reports by mainly summarizing and discussing some of the representative results, in order to promote further research in the relevant fields.