Advanced Oxygen Electrocatalysis Driven by Asymmetric Interfacial Sulfur Bridge Bonding

Abstract Rational modulation of interfacial electronic structure and active‐site cooperativity is essential for advancing bifunctional oxygen electrocatalysts in rechargeable aqueous zinc–air batteries (AZABs). Herein, a Co 9 S 8 /Fe 7 S 8 heterojunction encapsulated in porous N,S co‐doped carbon nanotubes (Co 9 S 8 /Fe 7 S 8 @NSCNTs) is constructed via a melamine‐assisted pyrolysis strategy to simultaneously enhance the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Asymmetric Co─S─Fe bonds at the heterointerface induce a bridge‐driven multi‐site synergy for promoting electron redistribution, surface polarity, and spatial activation of Co and Fe sites. By integrating sulfide heterointerfaces for ORR with the reconstructed (oxy)hydroxide surfaces for OER, this modulation lowers energy barriers of rate‐determining steps and enables reversible adsorption/desorption of oxygen intermediates, underscoring the critical role of asymmetric Co─S─Fe bridges in boosting bifunctional catalytic performance. Consequently, Co 9 S 8 /Fe 7 S 8 @NSCNTs exhibit remarkable catalytic efficiency and durability with an ORR half‐wave potential ( E 1/2 ) of 0.84 V and an OER overpotential of 353 mV. Rechargeable AZABs incorporating Co 9 S 8 /Fe 7 S 8 @NSCNTs achieve high peak power density (118.4 mW cm −2 ), large specific capacity (880.3 mAh g −1 ), and exceptional cycling stability (over 650 cycles). This work highlights robust sulfur‐bridge interface engineering for multi‐site activation and provides valuable insights for designing high‐performance oxygen electrocatalysts in next‐generation energy conversion and storage systems.