Exclusive Se‐O Coordination and Fe‐doping Complementation: A Catalytic Strategy for Enhanced Sulfur Redox in Li‐S Batteries

Abstract Developing efficient electrocatalysts to accelerate redox kinetics and suppress lithium polysulfides (LiPSs) shuttling remains a key challenge for lithium‐sulfur batteries (LSBs). Although transition‐metal‐oxides exhibit strong adsorption for the LiPSs, their application is impeded by sluggish Li 2 S conversion. Herein, a catalytic strategy is proposed for enhanced sulfur redox in LSBs by complementing exclusive Se‐O coordination and Fe‐doping in spinel Co 3 O 4 (Fe 0.1 Co 2.9 O 4 ‐Se) electrocatalyst. This engineered intersecting‐porous nanoarchitecture, fabricated via an etching‐carbonization method, facilitates electron/mass transport and exposes abundant electroactive sites. Fe 3+ substitution at octahedral Co 3+ sites synergizes with exclusive Se‐O coordination, narrows Co 3 O 4 ’s bandgap, and elevates the d‐band center, thereby enhancing conductivity and strengthening the LiPSs’ adsorption. Such a design promotes instantaneous nucleation of Li 2 S and reduces the bidirectional catalytic energy barrier for achieving superior catalytic activity, outperforming Se‐Fe 0.1 Co 2.9 O 4, where Se in oxygen‐vacancies‐sites coordinates with metal/oxygen ions. Consequently, the S/Fe 0.1 Co 2.9 O 4 ‐Se cathode delivers exceptional cycling stability with an ultralow capacity decay rate of 0.1054% per cycle over 500 cycles at 0.5 C. In a pouch cell with a high sulfur loading (6.1 mg cm −2 ) and lean electrolyte (E/S = 10 µL mg −1 ), it retains a capacity of 4.8 mAh cm −2 after 40 cycles. This work provides a new catalytic strategy for the design of high‐performance LSBs electrocatalysts.