Design and facile synthesis of defect rich C-MoS₂/rGO nanosheets for enhanced lithium-sulfur battery performance

Abstract

Reliable design and fabrication of advanced electrode materials are vital for developing lithium sulfur batteries. In this contribution, we report a simple one-step hydrothermal strategy for fabrication of a C-MoS2/rGO composite with both large surface area and high porosity. Double modified defect-rich MoS2 nanosheets are successfully prepared by introducing graphene oxide (GO) and amorphous carbon. The conductibility and structural stabilization of the cathodes can be improved owing to combination between the amorphous carbon and rGO, which could also restrain the dissolution of polysulfides. After annealing at different temperatures, it is found that the C-MoS2/rGO-6-S composite annealed at 600 oC delivers noticeably enhanced the performance of lithium-sulfur batteries, with a high specific capacity of 572 mAh·g-1 at 0.2C after 550 cycles, and 551 mAh·g-1 even at 2C, much better than those of MoS2-S nanosheets (249 mAh·g-1 and 149 mAh·g-1) and C-MoS2/rGO-S composite (334 mAh·g-1 and 382 mAh·g-1). Our intended electrode design protocol and annealing process may pave the way for the construction of other high-performance metal disulphide electrode for electrochemical energy storage.