Preparation of hierarchical porous graphene nanosheets with high specific surface area and their electrochemical behaviors in supercapacitors

Hierarchical porous graphene nanosheets (HPGNs) with high specific surface area have been prepared via a template method in which polystyrene microspheres was used as hard template. The as-prepared HPGNs showed a specific surface area as high as 1942 m(2) g(-1), considerably larger than those of porous graphene using polystyrene spheres as template reported before. The treating temperature of HPGNs is found to play an important role in determining their specific surface area and electrochemical performance. The HPGNs prepared at 700 degrees C showed an excellent rate performance, which could deliver a specific capacitance of as high as 112 Fg(-1) even at 16 Ag-1 based on two-electrode system. (C) 2016 Elsevier B.V. All rights reserved.