▎ 摘　　要

We developed a one-step hydrothermal method to assemble. graphene oxide (GO) sheets into hollow graphene spheres (HGSs), using only a GO/H2SO4 aqueous suspension as the starting material. Scanning electron microscope, focused ion beam scanning electron microscope and transmission electron microscope images show that the as-prepared HGSs vary from 1 to 3 gm in diameter and have a hollow interior structure. The as-prepared HGSs show a high capacitance of 207 F g(-1), as well as good rate capability and cycling stability when used as electrode materials for supercapacitors. (C) 2013 Elsevier Ltd. All rights reserved.