MoS2 nanorods with inner caves through synchronous encapsulation of sulfur for high performance Li-S cathodes

Abstract Lithium-sulfur (Li-S) batteries have become one of the most promising candidates for next-generation batteries owing to their high specific capacity, low cost, and environment-friendliness. Many efforts have been made to mitigate the “shuttle effect” through physical adsorption and chemical bonding. MoS2 has been proposed as a cathode material to provide effective anchoring sites for lithium polysulfides (LiPSs), but is still limited by its layer structure. Herein, we designed novel MoS2 nanorods with inner caves based on our previous work, and performed synchronous encapsulation of sulfur during the synthesis process. The outer MoS2 tubular shells physically inhibit the outward diffusion of polysulfide species while the inner particles chemically anchor the polysulfides to prevent shuttling. As the cathode matrix in Li-S batteries, the electrochemical results deliver a high initial discharge capacity of 1213 mAh g−1 for sulfur at 0.1 C. After cycling at 1 C for 300 cycles, the cells exhibit a capacity decay of only 0.076% per cycle and high average coulombic efficiency over 95%. The tubular MoS2 structure is an innovative and appealing design, which could be regarded as a prospective substrate for the improved performance of Li-S batteries.