Tuning dual-atom mediator toward high-rate bidirectional polysulfide conversion in Li-S batteries  

作　　者：Yifan Ding Zhongti Sun Jianghua Wu Tianran Yan Lin Shen Zixiong Shi Yuhan Wu Xiaoqing Pan Liang Zhang Qiang Zhang Jingyu Sun 

机构地区：[1]College of Energy,Soochow Institute for Energy and Materials Innovations,Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province,Soochow University,Suzhou 215006,Jiangsu,China [2]School of Materials Science and Engineering,Jiangsu University,Zhenjiang 212013,Jiangsu,China [3]National Laboratory of Solid-State Microstructures,Jiangsu Key Laboratory of Artificial Functional Materials,College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,Jiangsu,China [4]Institute of Functional Nano&Soft Materials,Jiangsu Provincial Key Laboratory for Carbon-Based Functional Materials and Devices,Soochow University,Suzhou 215006,Jiangsu,China [5]Department of Chemical Engineering,Tsinghua University,Beijing 100084,China

出　　处：《Journal of Energy Chemistry》2023年第12期462-472,I0012,共12页能源化学（英文版）

基　　金：supported by the National Natural Science Foundation of China(22179089);the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX23_3245);support from Suzhou Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies,Suzhou,China。

摘　　要：An emerging practice in the realm of Li-S batteries lies in the employment of single-atom catalysts(SACs)as effective mediators to promote polysulfide conversion,but monometallic SACs affording isolated geometric dispersion and sole electronic configuration limit the catalytic benefits and curtail the cell performance.Here,we propose a class of dual-atom catalytic moieties comprising hetero-or homo-atomic pairs anchored on N-doped graphene(NG)to unlock the liquid–solid redox puzzle of sulfur,readily realizing Li-S full cell under high-rate-charging conditions.As for Fe-Ni-NG,in-depth experimental and theoretical analysis reveal that the hetero-atomic orbital coupling leads to altered energy levels,unique electronic structures,and varied Fe oxidation states in comparison with homo-atomic structures(FeFe-NG or Ni-Ni-NG).This would weaken the bonding energy of polysulfide intermediates and thus enable facile electrochemical kinetics to gain rapid liquid-solid Li_(2)S_(4)?Li_(2)S conversion.Encouragingly,a Li-S battery based on the S@Fe-Ni-NG cathode demonstrates unprecedented fast-charging capability,documenting impressive rate performance(542.7 mA h g^(-1)at 10.0 C)and favorable cyclic stability(a capacity decay of 0.016%per cycle over 3000 cycles at 10.0 C).This finding offers insights to the rational design and application of dual-atom mediators for Li-S batteries.

关 键 词：Li-S batteries Reaction kinetics Dual-atom Rate-determining step High-rate performance 

分 类 号：TM912[电气工程—电力电子与电力传动]