Reinforcing the Adsorption and Conversion of Polysulfides in Li−S Battery by Incorporating Molybdenum into MnS/MnO Nanorods

Abstract

AbstractThe Sabatier principle suggests that an excessive adsorption of lithium polysulfides (LiPSs) by metal compounds may hinder their conversion in the absence of a conversion module. Therefore, it is imperative to establish a synergetic effect mechanism between “strong adsorption” and “rapid conversion” for LiPSs. To achieve this coexistence, a molybdenum‐doped MnS/MnO@C porous structure is designed as a multifunctional coating on the polypropylene (PP) separator. The incorporation of MnS/MnO@C enhances the adsorption capacity towards LiPSs, while molybdenum facilitates subsequent conversion. Benefiting from the synergistic effect of each component and its large specific surface area, the cell with Mo‐doped MnS/MnO@C coating achieves smooth adsorption‐diffusion‐conversion processes and exhibits an appreciable rate performance with outstanding cycling stability. Even when sulfur loading increases to 9.68 mg cm−2, the modified battery delivers an excellent initial areal capacity of 11.69 mAh cm−2 and maintains 6.97 mAh cm−2 after 50 cycles at 0.1 C. This study presents a promising approach to simultaneously accomplish “strong adsorption” and “rapid conversion” of polysulfides, offering novel perspectives for devising dual‐functional modified separators.