UV-assisted reduction of graphene oxide on Ni foam as high performance electrode for supercapacitors

Abstract

Here, we present a universal route for the rational design of graphene-based supercapacitor electrode. In this method, graphene oxide film (GO) deposited on Ni foam was directly reduced in a short times by light reduction process using a high-pressure Hg lamp. UV-assisted reduction of GO on Ni foam is a green, rapid and facile way while avoiding the use of toxic chemicals and help to simplify the fabrication steps of supercapacitor electrodes by comparison of traditional fabrication procedures. The photoreduction graphene (PrGO) sheets were grown on Ni foam without any conductive agents and polymer binders, and thus to form a composite structure with continuous and interconnected network, which is beneficial to greatly reduce contact resistance between PrGO sheets and metal current collector and facilitates the efficient access of electrolyte ions to the graphene surface and shorten the ion diffusion path. As applied in supercapacitors, the resulting PrGO electrode shows ideal and reversible capacitive behaviour and excellent electrochemical performance. Moreover, this strategy affords a simple and highly versatile route for fabricating graphene electrode materials for supercapacitors.