Construction of defective MoxW1-xS2/Cu7.2S4 polyhedral heterostructures for fast sodium storage

作者:Liu, Xiaozhao; Cheng, Qian; Zhong, Wentao; Deng, Qiang; Yang, Cuiyun; Liu, Yuqiao; Hu, Junhua; Yang, Chenghao*
来源:Chemical Engineering Journal, 2023, 451: 138645.
DOI:10.1016/j.cej.2022.138645

摘要

Molybdenum disulfide (MoS2) has great potential applications for Na+-storage mainly for its high capacity and layered graphene-like structure. However, large volume changes and poor electrochemical kinetics restrict the electrochemical performances of metal chalcogenides. Thus, defective MoxW1-xS2/Cu(7.2)S4 (MWS/CS) polyhedrons (DPs) composed of heterostructured MWS/CS nanosheets have been synthesized by a liquid chemical technique. The heterointerface formed between MWS and CS is mainly ascribed to its high and stable performance by stabilizing the electrochemical reaction products, promoting the electrons and Na+ ions migration and buffering the volume expansion. Eventually, MWS/CS DPs displays a high reversible capacity (566 mAh/g at 0.2 A/g) with upper initial coulombic efficiency of 96.4 %, good rate capability (459.9, 419.2 and 417.2 mAh/g at 1.0, 5.0, 10.0 A/g, separately) and excellent cycling stability (553.1 mAh/g at 5.0 A/g after 1000 cycles).