Built-in electric field accelerated polysulfide conversion for advanced lithium-sulfur batteries

Abstract

Lithium-sulfur (Li-S) batteries are promising candidates for next-generation energy storage devices, but they still suffer by the shuttle effect and sluggish conversion of lithium polysulfides (LiPSs). Herein, we proposed a NiO-Co9S8 p-n junction heterostructure as a sulfur host material, in which built-in electric field traps while NiO catalytically converts LiPSs to suppress their dissolution in the electrolyte. Li-S batteries based on the NiO-Co9S8/rGO as a sulfur host material can exhibit high capacity, excellent rate performance (653.2 mAh g−1 at 3 C) and an ultralow capacity decay rate (0.059% per cycle over 1000 cycles at 1 C). This work sheds light on heterostructure design for Li-S batteries approaching practical application.