Synergistic Effect of VS 2 /MoS 2 as an Electrocatalyst for Accelerating Polysulfide Conversion in Lithium–Sulfur Batteries

High Resolution Image Download MS PowerPoint Slide The shuttle effect of soluble lithium polysulfides (LiPSs) poses a formidable challenge that severely compromises the electrochemical performance of lithium–sulfur (Li–S) batteries. This study introduces a unique lamellar stacked VS 2 /MoS 2 nanoflower structure, prepared using a simple one-step hydrothermal synthesis method, to reduce the polysulfide shuttle effect in Li–S batteries. VS 2 /MoS 2 synergistically boosts LiPS conversion, combining VS 2 ’s high conductivity with the catalytic activity of MoS 2, as confirmed by density functional theory (DFT) calculations. Electrochemical testing demonstrated excellent performance for VS 2 /MoS 2 @S cathodes. It delivers an initial discharge-specific capacity of 1353 mAh g –1 at 0.1 C, and at 1 C, the capacity remains as high as 925 mAh g –1 . At 0.2 C, the initial discharge-specific capacity is 1299 mAh g –1, and the capacity retention rate reaches 55% after 500 cycles. This study provides valuable insights into designing and engineering high-performance heterostructures to enhance the adsorption of LiPSs and improve the reaction kinetics in Li–S batteries.