Lewis Acidic/Basic Oxides Modulated Cu 3 P for Efficient Lithium Polysulfide Electrocatalytic Conversion

Abstract Addressing sluggish reaction kinetics and the shuttling of lithium polysulfides (LiPSs) requires the development of efficient electrocatalysts in lithium–sulfur (Li─S) batteries. Here, novel Cu 3 P heterostructure catalysts is synthesized, modulated by Lewis acidic/basic metal oxides (Cu 3 P‐MO, where M = Zn or Mg), in order to facilitate the conversion of LiPSs. Specifically, the Lewis acidic oxide ZnO in Cu 3 P‐ZnO captured electrons from Cu 3 P, resulting in an upward shift of the d‐band center of Cu ( E Cu‐3d ). This enhanced the adsorption of Lewis basic polysulfides, reduced the activation energy of the polysulfide reduction reaction, and significantly accelerated the reaction kinetics. As anticipated, the Cu 3 P‐ZnO catalyst on porous carbon (Cu 3 P‐ZnO/PC) effectively promoted the electrocatalytic conversion and suppressed the shuttling of LiPSs. The Cu 3 P‐ZnO/PC@S cathode demonstrated exceptional cycling stability, maintaining performance over 2000 cycles at 4 C with an ultralow decay rate of 0.014% per cycle, achieving a remarkable rate capability of 665 mAh g −1 at 8 C. Further, in situ X‐ray diffraction analysis is employed to elucidate the conversion mechanisms of sulfur species during the charge/discharge process. Notably, the Li─S pouch cell equipped with the Cu 3 P‐ZnO/PC@S cathode delivered a high energy density of 415.8 Wh kg −1 .