Strong d−π Orbital Coupling of Co–C 4 Atomic Sites on Graphdiyne Boosts Potassium–Sulfur Battery Electrocatalysis

作者：Shipeng Zhang, Ya Kong, Yu Gu, Ruilin Bai, Menggang Li, Shuoqing Zhao, Mingze Ma, Zhen Li, Lingyou Zeng, Daping Qiu, Qinghua Zhang, Mingchuan Luo, Lin Gu, Yan Yu, Shaojun Guo, Jin Zhang · 发表于：Journal of the American Chemical Society · 年份：2024 · DOI：10.1021/jacs.3c09533 · 被引用次数：78 · 研究领域：Advanced Battery Materials and Technologies、Advancements in Battery Materials、Inorganic Chemistry and Materials

Potassium–sulfur (K–S) batteries are severely limited by the sluggish kinetics of the solid-phase conversion of K 2 S 3 /K 2 S 2 to K 2 S, the rate-determining and performance-governing step, which urgently requires a cathode with facilitated sulfur accommodation and improved catalytic efficiency. To this end, we leverage the orbital-coupling approach and herein report a strong d−π coupling catalytic configuration of single-atom Co anchored between two alkynyls of graphdiyne (Co-GDY). The d−π orbital coupling of the Co–C 4 moiety fully redistributes electrons two-dimensionally across the GDY, and as a result, drastically accelerates the solid-phase K 2 S 3 /K 2 S 2 to K 2 S conversion and enhances the adsorption of sulfur species. Applied as the cathode, the S/Co-GDY delivered a record-high rate performance of 496.0 mAh g –1 at 5 A g –1 in K–S batteries. In situ and ex situ characterizations coupling density functional theory (DFT) calculations rationalize how the strong d−π orbital coupling of Co–C 4 configuration promotes the reversible solid-state transformation kinetics of potassium polysulfide for high-performance K–S batteries.