Catalyzing the polysulfide conversion by using iron sulfide as self-supported electrode

Polysulfide, as the discharge products of the lithium–sulfur batteries, could easily dissolve into the electrolyte and cause severe shuttle effect between the cathode and anode side. This phenomenon will lead to rapid capacity fading during the electrochemical cycles and poor cycling stability. Therefore, it is important to mitigate the polysulfide shuttle effect and accelerate the polysulfide conversion in the lithium–sulfur batteries. Herein, iron sulfide nanosheets were successfully prepared and developed as sulfur host materials in the lithium–sulfur batteries. Due to the presence of the iron sulfide, the as-prepared iron sulfide/sulfur composites exhibit superior electrochemical performance, including high specific capacity, high rate performance, and stable cycling performance. This is attributed the efficient polysulfide conversion catalyzed by iron sulfide.