Stable immobilization of lithium polysulfides using three‐dimensional ordered mesoporous Mn₂O₃ as the host material in lithium–sulfur batteries

Abstract Lithium–sulfur batteries (LSBs) have drawn significant attention owing to their high theoretical discharge capacity and energy density. However, the dissolution of long‐chain polysulfides into the electrolyte during the charge and discharge process (“shuttle effect”) results in fast capacity fading and inferior electrochemical performance. In this study, Mn₂O₃ with an ordered mesoporous structure (OM‐Mn₂O₃) was designed as a cathode host for LSBs via KIT‐6 hard templating, to effectively inhibit the polysulfide shuttle effect. OM‐Mn₂O₃ offers numerous pores to confine sulfur and tightly anchor the dissolved polysulfides through the combined effects of strong polar–polar interactions, polysulfides, and sulfur chain catenation. The OM‐Mn₂O₃/S composite electrode delivered a discharge capacity of 561 mA h g⁻¹ after 250 cycles at 0.5 C owing to the excellent performance of OM‐Mn₂O₃. Furthermore, it retained a discharge capacity of 628 mA h g⁻¹ even at a rate of 2 C, which was significantly higher than that of a pristine sulfur electrode (206 mA h g⁻¹). These findings provide a prospective strategy for designing cathode materials for high‐performance LSBs.