Hierarchically porous graphene for batteries and supercapacitors

Abstract

As energy consumption rapidly increases, energy storage devices that are low-cost, environmentally friendly and have a long life span are imperative. Recently, hierarchically porous graphene (HPG) based electrode materials have received widespread attention due to their unique porous structure and outstanding intrinsic properties such as high specific capacity, good rate capability, being pollution-free, and excellent conductivity. The hierarchically porous structure is beneficial for the charge transfer at the electrode/electrolyte interface and ion diffusion, and it can also accommodate volume changes during cycling. Moreover, the existence of a large number of defects in the basal plane of graphene increases the number of electrochemically active reversible storage sites. These advantages make HPG a promising material for electrochemical energy storage devices with flexible, stable, inexpensive, high gravimetric and volumetric current density. This perspective paper focuses on the recent works on HPG based materials and their applications in batteries (such as lithium-ion batteries and post lithium-ion batteries) and supercapacitors.