▎ 摘 要
Rechargeable lithium-sulfur batteries are deemed to be a promising energy supply to next-generation high energy power system, yet dissolution of lithium polysulfides in the electrolyte leads to poor cycling performance. Here, we report an approach to assemble graphene and polydopamine double-wrapped porous carbon/sulfur (GN-PD-PC-S) for lithium-sulfur batteries. Remarkably, the double-wrapping graphene and polydopamine further help confine the sulfur and polysulfides inside the mesopores and micropores of porous carbon. Moreover, the hierarchical porous structures provide a conductive network for electron transfer and facilitate the effective accommodation of the volume change of sulfur. The GN-PD-PC-S cathode presents an excellent cycling stability of 821 mAh g(-1) after 100 cycles, with a favorable high-rate capability of 496 mAh g(-1) at a current density of 2 A g(-1). Our results indicate the importance of chemically synergistic effect of polymer and carbon in the electrode system for achieving high-performance electrodes in rechargeable lithium-sulfur batteries.