Dong Yangyang, Cai Dong, Li Tingting, Yang Shuo, Zhou Xuemei, Ge Yongjie, Tang Hao, Nie Huagui, Yang Zhi
Key Laboratory of Carbon Materials of Zhejiang Province, Wenzhou University, Wenzhou 325035, China.
College of Electrical and Electronic Engineering, Wenzhou University, Wenzhou 325035, China.
ACS Nano. 2022 Apr 26;16(4):6414-6425. doi: 10.1021/acsnano.2c00515. Epub 2022 Apr 11.
The key challenges facing the commercialization of lithium-sulfur (Li-S) batteries are shortening the lithium polysulfide (LiPS) intermediate existence time while accelerating solid-phase conversion reactions. Herein, inspired by highly efficient natural enzymes with Fe/N active sites for oxygen reduction reactions, we report a periodic expansion catalysis concept, i.e., Ru and P synergic stereoselectivity, for designing sulfur reduction reaction (SRR) catalysts. As a proof of concept, a RuP-configuration molecular catalyst was exploited to assemble an interlayer in Li-S batteries that adsorbs LiPSs, optimizes Li migration paths, and catalyzes SRRs. Comprehensive investigation identified the elimination of steric hindrance and strong electron orbital couplings between metallic d band and nonmetallic p band as the main contributing factors of PEC for the SRRs. As a result, the Li-S battery with ∼0.5 wt % catalyst additive showed enhanced cycling stability even under a high sulfur loading (6.5 mg cm) and low electrolyte/sulfur ratio (9 μL mg).
锂硫（Li-S）电池商业化面临的关键挑战是缩短多硫化锂（LiPS）中间产物的存在时间，同时加速固相转化反应。在此，受具有用于氧还原反应的Fe/N活性位点的高效天然酶启发，我们报道了一种周期性扩展催化概念，即Ru和P协同立体选择性，用于设计硫还原反应（SRR）催化剂。作为概念验证，利用RuP构型分子催化剂在Li-S电池中组装一个夹层，该夹层吸附LiPSs，优化Li迁移路径，并催化SRR。综合研究确定，消除空间位阻以及金属d带和非金属p带之间强烈的电子轨道耦合是SRR的PEC的主要促成因素。结果，即使在高硫负载（6.5 mg cm）和低电解质/硫比（9 μL mg）下，添加约0.5 wt%催化剂的Li-S电池仍表现出增强的循环稳定性。
