Accelerated redox conversion by CoMoS₃/CoS synergistic interactions for high-performance lithium sulfur batteries

While lithium-sulfur battery has received widespread attention as energy storage devices, its performance is still limited by the sluggish redox kinetics, shuttle effect, and the stability of electrode materials etc. In this work, to address these problems, CoMoS3/CoS composite was synthesized and as cathode materials of lithium sulfur (Li-S) batteries. CoMoS3 buffers the volume expansion during charging/discharging, and provides abundant active sites for the redox reaction of sulfur. The highly conducive flake CoS has a strong adsorption effect for polysulfides. The synergistic effect of composite promotes the rapid charge transfer and redox kinetics. The discharge capacity of the CoMoS3/CoS electrode is 404 mAh g(-1) after 600 cycles at 1C, exhibiting an improved capacity decay (0.053% per cycle), which is obviously better than that of CoMoS3 electrode. The CoMoS3/CoS composite structure proposed in this paper can effectively restrain shuttle effect and thus improve battery performance, providing a feasible implementation route for the design of host materials.