▎ 摘　　要

Aiming at preventing restacking of individual graphene sheets by using a simple green hydrothermal route, we have introduced carbon nanotubes to act as the spacer in fabricating a three-dimensional (3-D) hierarchical structure with graphene sheets. These 3-D hierarchical structure materials have been used to fabricate supercapacitor devices, and a high specific capacitance of 318 F/g for graphene with an energy density of 11.1 (W h)/kg has been achieved.