▎ 摘　　要

Electrode materials with macroporous structures have desirable structural advantages, which can provide excellent reaction sites for electrons and ions. In this study, a novel macroporous nanostructure is synthesized utilizing N-doped hollow carbon spheres and ZIF-67 derived Co9S8 embedded in graphene (GH@NC@Co9S8). This macroporous nanostructure can maximize the entire surface area, which provides a favorable transport environment for the electrons and ions of the electrolyte. Furthermore, in situ grown Co9S8 polyhedra derived from ZIF-67 can improve the reactivity and specific capacity of the composite due to their amorphous phase and hollow three-dimensional structure. The as-prepared GH@NC@Co9S8 acts as a binder-free electrode for supercapacitors; it shows a high volumetric capacitance of 842.4 F cm(-3) at a current density of 1 A g(-1). An asymmetric supercapacitor fabricated with GH@NC@Co9S8 (positive electrode) and GH@NC (negative electrode) shows a superb volumetric energy density of 28.7 W h L-1 at a high power density of 971.9 W L-1 and long cycle life (95.8% capacity retention after 8000 cycles). This device has great practical value in electrochemical energy storage.