Single‐Atomic Fe‐S ₃ ‐Mo Sites Triggered Fast Redox Conversion in Li‐S Batteries

ABSTRACT Lithium‐sulfur (Li‐S) batteries are widely recognized as one of the most promising next‐generation energy storage technologies owing to their high theoretical energy density (∼2600 Wh kg ⁻¹ ), cost‐effectiveness, and environmental friendliness. However, their practical application is severely hindered by slow electrochemical reaction kinetics and the detrimental shuttle effect of lithium polysulfides (LiPSs). Single‐atom catalysts (SACs), characterized by nearly 100% atomic utilization and high catalytic activity, have been extensively investigated in sulfur cathodes to accelerate sulfur redox reactions. Nevertheless, individual single‐atom sites usually exhibit limited catalytic efficacy for multi‐step sulfur conversion processes, leading to suboptimal practical performance. Herein, we construct a structure comprising atomically dispersed Fe single atoms anchored on MoS ₂ nanosheets (FeSA‐MoS ₂ @NC), with Fe atoms stabilized at Mo‐top sites via Fe‐S ₃ coordination. This Fe‐S ₃ ‐Mo interfacial coupling induces electronic redistribution and enhances host‐guest interactions, thereby significantly boosting both catalytic and adsorption capabilities compared to single‐component systems. As a result, the S/FeSA‐MoS ₂ @NC cathode exhibits superior electrochemical performance, enabling lean‐electrolyte pouch cells to achieve a discharge capacity of 1.72 Ah with an energy density of 302 Wh kg ⁻¹ based on the total cell mass. This work provides a novel strategy for engineering single‐atom catalysts and offers valuable insights into the advancement of high‐performance Li‐S batteries.