Forming SnS@C/MoS2 nanotubes with high specific surface area via self-sacrificing template method as superior performance anode for lithium-ion batteries

Abstract

A carbon layer usually covers the outside of SnS/MoS₂ nanosheets produced by a traditional C-layer cladding process, resulting in a material with a lower specific surface area and fewer active sites. Therefore, it is difficult for these as-obtained SnS and MoS₂ materials to be directly employed as electrode materials. There is a great need to develop a new C-layer coating process that can effectively coat active materials and simultaneously increase the specific surface area. In this study, novel SnS@C/MoS₂ nanotubes were designed and synthesized by a self-sacrificing template method (SSTM). Specifically, MoO₃ nanoribbons were first coated with Sn to produce Sn-MOF, and SnS@C/MoS₂ nanotubes with a particular nanosheet architecture preserved were achieved via an elegant SSTM vulcanization strategy. This SSTM preparation method not only retains the nanosheet microstructure of the surface but also leaves a thin layer of amorphous carbon on the surface, which greatly improves the conductivity and effectively improves the cycling stability. In addition to above-mentioned advantages, there is a synergistic effect between the various components of the SnS@C/MoS₂ nanotubes, which has a positive effect on the electrochemical performance. When used as the anode of a lithium-ion battery (LIB), the SnS@C/MoS₂ composite can maintain a specific discharge capacity of 970.9 mAh g⁻¹ after 500 cycles at a current density of 1 A g⁻¹, and a specific discharge capacity of 778.1 mAh g⁻¹ even after 1000 cycles at a current density of 2 A g⁻¹. This method provides a reference for the synthesis of other nanostructured materials.