Interfacial Build‐In Electric Field Unlocking Hetero‐Architectured CoO‐Co ₃ O ₄ Nanotubes Toward High‐Performance Li‐S Batteries

Abstract The sluggish redox kinetics and intrinsic dissolution of lithium polysulfides (LiPSs) critically hinder the desirable commercialization of Li‐S batteries (LSBs). Purposeful modification of separators with multi‐functional materials brings enormous room for both efficiently restraining the dissolution and enhancing the solid‐liquid‐solid conversion kinetics of LiPSs. For this, herein, hetero‐architectured CoO‐Co ₃ O ₄ hollow nanotubes (HNTs) are elaborately designed and fabricated via a self‐sacrifice template methodology to modify the polypropylene (PP) separator for advanced LSBs. Besides the robust physico chemical adsorption, the endogenous CoO‐Co ₃ O ₄ heterojunction, as authenticated by theoretical calculations and experimental verification, spontaneously creates an interfacial built‐in electric field, which simultaneously enhances the active sites, accelerates the bi‐directional sulfur conversion, and favors the fast electron/ion transport. Thanks to successful realization of the synergistic “electrostatic capture‐energy barrier regulation‐directional conversion” effect, LSBs with the hetero CoO‐Co ₃ O ₄ HNTs modified PP separator exhibit significantly improved electrochemical performance with the long‐duration cycling stability for 1000 cycles at 5 C, and a large capacity of 631.5 mAh g ⁻¹ even at a high sulfur loading (5 mg cm ^‒2 ) and low electrolyte/sulfur ratio (8.0 µL mg ⁻¹ ). More essentially, our contribution here offers a viable avenue for up‐and‐coming hetero‐catalyst functionalized separator platforms toward next‐generation LSBs and beyond.