Delocalized Isoelectronic Heterostructured FeCoO x S y Catalysts with Tunable Electron Density for Accelerated Sulfur Redox Kinetics in Li‐S batteries

作者：Peng Chen, Tianyi Wang, Di He, Ting Shi, Manfang Chen, Kan Fang, Hongzhen Lin, Jian Wang, Chengyin Wang, Huan Pang · 发表于：Angewandte Chemie International Edition · 年份：2023 · DOI：10.1002/anie.202311693 · 被引用次数：81 · 研究领域：Advanced Battery Materials and Technologies、Advancements in Battery Materials、Advanced battery technologies research

Abstract High interconversion energy barriers, depressive reaction kinetics of sulfur species, and sluggish Li + transport inhibit the wide development of high‐energy‐density lithium sulfur (Li−S) batteries. Herein, differing from random mixture of selected catalysts, the composite catalyst with outer delocalized isoelectronic heterostructure (DIHC) is proposed and optimized, enhancing the catalytic efficiency for decreasing related energy barriers. As a proof‐of‐content, the FeCoO x S y composites with different degrees of sulfurization are fabricated by regulating atoms ratio between O and S. The relationship of catalytic efficiency and principal mechanism in DIHCs are deeply understood from electrochemical experiments to in situ/operando spectral spectroscopies i.e., Raman, XRD and UV/Vis. Consequently, the polysulfide conversion and Li 2 S precipitation/dissolution experiments strongly demonstrate the volcano‐like catalytic efficiency of various DIHCs. Furthermore, the FeCoO x S y ‐decorated cell delivers the high performance (1413 mAh g −1 at 0.1 A g −1 ). Under the low electrolyte/sulfur ratio, the high loading cell stabilizes the areal capacity of 6.67 mAh cm −2 at 0.2 A g −1 . Impressively, even resting for about 17 days for possible polysulfide shuttling, the high‐mass‐loading FeCoO x S y ‐decorated cell stabilizes the same capacity, showing the practical application of the DIHCs in improving catalytic efficiency and reaching high electrochemical performance.