Cascade Anchoring Engineering of Single‐Atom Fe on N/P Co‐Doped Hierarchical Porous Carbon Toward High‐Energy‐Density and Remarkably Stable Lithium‐Sulfur Batteries

ABSTRACT Lithium‐sulfur batteries (LSBs) have been considered as one of the most promising next‐generation energy storage systems, however, they suffer from poor conductivity of sulfur, shuttling effects of polysulfides, and sluggish reaction kinetics. In this work, a cascade anchoring strategy was employed to synthesize a Fe‐N/P co‐doped porous carbon catalyst (Fe‐N/P‐PC) with high single‐atom Fe loading (9.0 wt.%). The strategy combines spatial confinement, glucose‐assisted chelation and pyrolysis to form stable Fe‐(N/P) 4 ‐C sites within a hierarchical porous structure. The resulting S@Fe‐N/P‐PC as cathode for LSBs delivers high capacities of 1263.5 mAh g −1 at 0.2 C and 530.0 mAh g −1 at 8 C, and maintains 701.4 mAh g −1 after 1000 cycles at 1 C. Under high sulfur loading of 6.8 mg cm −2 and lean electrolyte of 5.9 µL mg −1 , it achieves a high areal capacity of 5.38 mAh cm −2 with 87.8% initial capacity retention after 200 cycles at 0.1 C. A 52.1 mg sulfur pouch cell exhibits a high initial energy density of 410.6 Wh kg −1 and 83.3% retention after 350 cycles, demonstrating its high practical potential.