标题：Conductive and Catalytic VTe2@MgO Heterostructure as Effective Polysulfide Promotor for Lithium–Sulfur Batteries
作者：Menglei Wang1, Yingze Song1, Zhongti Sun1, Yuanlong Shao2, Chaohui Wei1, Zhou Xia1, Zhengnan Tian1, Zhongfan Liu1,3,4, and Jingyu Sun1,3
单位：1. College of Energy, Soochow Institute for Energy and Materials Innovations (SIEMIS), Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies, Soochow University, Suzhou 215006, P. R. China
2. College Physical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
3. Beijing Graphene Institute (BGI), Beijing 100095, P. R. China
4. Center for Nanochemistry (CNC), College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
摘要：Lithium–sulfur (Li–S) batteries are recognized as one of the most promising energy storage systems due to the high energy density and cost-effectiveness. However, their practical implementation has still been handicapped due to notorious lithium polysulfide (LiPS) shuttle anddepressed sulfur redox kinetics. It is therefore desirable to exploit key mediators synergizing electrical conductivity and electrocatalytic activity for the cathode. Herein, we report the employment of atmospheric pressure chemical vapor deposition to harness the efficient and controllable synthesis of metallic VTe2 over particulated MgO substrates, which has scarcely been demonstrated by conventional wet-chemical synthetic routes by far. Thus-derived VTe2@MgO heterostructure as an efficient promotor enables effective regulation of LiPSs with respect to polysulfide capture/conversion and Li2S decomposition. As a result, S/VTe2@MgO cathode with a sulfur loading of 1.6 mg cm–2 harvests long-term cyclability with a negligible capacity decay of 0.055% per cycle over 1000 cycles at 1.0 C. Even at a sulfur loading of 6.9 mg cm–2, the cathode still delivers electrochemical performances that can rival the state-of-the-art high-loading counterparts. Our work might offer a feasible solution for developing heterostructured promotors with multifunctionality and electrocatalytic activity for high-performance Li–S batteries.