N-doped porous carbon heterostructure from ZCSCF@MXene embedded on cellulose fiber for high-performance lithium storage

Heterojunction electrode materials derived from MOFs have been shown to effectively improve capacity and rate performance. In this paper, ZnS/Co 9 S 8 (ZCS) heterojunction is successfully embedded in the three-dimensional spatial structure composed of cellulose fiber and MXene, forming a unique composite system by solvothermal method and electrostatic self-loading technology. ZCS particles are well dispersed to the fiber substrate and MXene, exhibited a large specific surface area of 54.80 m 2  g −1 and high level of structural defects, which providing abundant active sites for Li + . The Li ion battery prepared by ZnCoSCF@MXene (ZCSCF@MXene) exhibited high specific capacity of 1549.1 mAh g −1 at 1 A g −1 and excellent magnification performance of 632.3 mAh g −1 at 6.4 A g −1 . The outstanding performance of the ZCSCF@MXene electrode is due to multiple factors, such as the intrinsic electric field created by the ZCS heterostructure, the nitrogen-doped cellulose fiber matrix expanding the contact area between the electrode material and the electrolyte, and the MXene provides a swift route for electron transport, which not only boosts electron dynamics but also successfully prevents the aggregation of ZCS. This paper provides a reference for the composite of heterostructures with cellulose fiber, and provide a new idea for the design of negative electrode materials with high performance metal sulfide heterostructures.