Regulating the polysulfide redox conversion by iron phosphide nanocrystals for high-rate and ultrastable lithium-sulfur battery

A novel iron phosphide nano-catalyst is proposed to chemically anchor polysulfides, regulate their conversion, and promote the Li2S deposition. The obtained FeP nanocrystals with intrinsic polysulfide affinity and catalyst activity suppress the polysulfide dissolution and enhance the redox reaction kinetics, enabling ultra-stable cycling of 0.04% capacity decay per cycle and excellent rate performance with 613.1 mA h g−1 at 3 C.264