▎ 摘　　要

Well-intergrown nanocrystals of zeolitic imidazolate frameworks (ZIF-8) supported on three-dimensional (3D) graphene were prepared by a counter diffusion technique. The incorporation of ZIF-8 crystals greatly improves the surface areas of the graphene composites. The carbonized graphene-ZIF composites with hierarchical pore structures showed high electrochemical capacitance and good stability. This work provides an efficient method to synthesize porous carbon materials with high capacitance. Published by Elsevier Ltd.