Built‐In Interfacial Electric Fields Resolve the Adsorption‐Kinetics Trade‐Off in Lithium‐Sulfur Batteries

ABSTRACT The development of practical lithium‐sulfur (Li─S) batteries is fundamentally impeded by an intrinsic trade‐off between polysulfide immobilization and sulfur redox kinetics: strong adsorption suppresses polysulfide shuttling but impedes charge transfer, whereas conductive hosts favor fast kinetics yet fail to confine soluble species. Here, we demonstrate that built‐in interfacial electric fields can help alleviate this long‐standing dilemma by regulating sulfur redox chemistry through a distinct interfacial mechanism. By constructing a metallic‐polar NiTe ₂ ‐CoO heterostructure, spontaneous electron transfer across the heterointerface generates a localized electric field, which, together with moderate interfacial chemical interactions, stabilizes polysulfides and supports more favorable sulfur‐conversion kinetics. Comprehensive experimental characterizations combined with density functional theory (DFT) calculations reveal that the NiTe ₂ ‐CoO heterointerface simultaneously modulates polysulfide chemisorption and accelerates multistep sulfur redox reactions, enabling fast Li ₂ S nucleation and efficient Li ₂ S oxidation. Benefiting from these interfacial effects and a hierarchical hollow architecture that maximizes active heterointerfaces, Li─S cells exhibit accelerated redox kinetics, high sulfur utilization, and exceptional cycling stability under high sulfur loading and lean electrolyte conditions. This work establishes interfacial electric‐field modulation as a general design principle for resolving the adsorption‐kinetics trade‐off in Li─S batteries.