Pvp-Assisted Preparation of Ultrathin Mos2 Nanosheets Carbon Nanotube Composites as Sulfur Cathodes for the Catalytic Conversion of Lithium Polysulfide

Slow reaction kinetics, low sulfur utilization, and the shuttle effect severely affect the electrochemical properties of lithium-sulfur battery (LSB). Therefore, the design of sulfur carriers with high catalysis, strong adsorption and rational structure are the key to solve these problems. In this study, the sulfur carrier was synthesized by a PVP-assisted one-step hydrothermal method. In this carrier material, ultrathin molybdenum disulfide (ut-MoS2) nanosheets were uniformly dispersed in the three-dimensional skeleton of carbon nanotubes (CNTs). Among them, CNTs could form a three-dimensional conductive network, which not only accelerates the electron/ion transport, but also increases the electrical conductivity. The ut-MoS2 nanosheets exposed more catalytically active sites, which improved the adsorption and catalytic conversion of LiPSs and effectively suppressed the shuttle effect. The initial specific capacity of the S@ut-MoS2/CNTs cathode at 0.1C is 1302 mAh g-1. After 300 cycles at 0.2 C, the capacity decay rate is 0.072%. In addition, with a high sulfur surface loading of 4.8 mg cm-2, the S@ut-MoS2/CNTs cathode have a discharge specific capacity of 585 mAh g-1 after 300 cycles at 0.2 C. This study provides a way to explore the construction of new sulfur carriers for LSB.