Hierarchically porous graphene-based hybrid electrodes with excellent electrochemical performance

Abstract

A new structure of hierarchically porous graphene–nickel hydroxide (Ni(OH)₂) hybrid, which contains both in-plane mesopores and out-of-plane meso/macropores, has been fabricated by a facile one-step method using holey graphene as a framework structure and Ni(OH)₂ as a “spacer”. The aforementioned two kinds of pores facilitate the kinetics of processes occurring in an electrode without compromising its conductivity, and assure high charge storage capacity and rate capability. The material displays an excellent rate capability, high stability and its capacitance is among the top values for powder-based supercapacitors. This study paves the way towards the development of feasible strategies for tailoring the porosity of graphene-based structures for advanced energy storage devices.