Construction of VS2/VOx Heterostructure via Hydrolysis‐Oxidation Coupling Reaction with Superior Sodium Storage Properties

• Published in: Advanced functional materials 2023-03, Vol.33 (12), p.n/a
• Main Authors: Zhang, Yuxiang, Chen, Yangziyu, Jiang, Yan, Wang, Jing, Zheng, Xiangyi, Han, Bo, Xia, Kaisheng, Gao, Qiang, Cai, Zhao, Zhou, Chenggang, Sun, Ruimin
• Format: Article
• Language: English
• Subjects: anode materials; Aqueous solutions; Construction; Coupling; Cycles; Density functional theory; Electric fields; Electrical resistivity; Electrodes; Electron transfer; Heterostructures; Hydrolysis; hydrolysis‐oxidation coupling reactions; Materials science; Metal sulfides; Oxidation; Reaction kinetics; Sodium; sodium‐ion batteries; Stability; Transition metals; VS 2/VO x
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202212785

Heterostructure engineering is one of the most promising modification strategies for reinforcing Na+ storage of transition metal sulfides. Herein, based on the spontaneous hydrolysis‐oxidation coupling reaction of transition metal sulfides in aqueous media, a VOx layer is induced and formed on the surface of VS2, realizing tight combination of VS2 and VOx at the nanoscale and constructing homologous VS2/VOx heterostructure. Benefiting from the built‐in electric field at the heterointerfaces, high chemical stability of VOx, and high electrical conductivity of VS2, the obtained VS2/VOx electrode exhibits superior cycling stability and rate properties. In particular, the VS2/VOx anode shows a high capacity of 878.2 mAh g−1 after 200 cycles at 0.2 A g−1. It also exhibits long cycling life (721.6 mAh g−1 capacity retained after 1000 cycles at 2 A g−1) and ultrahigh rate property (up to 654.8 mAh g−1 at 10 A g−1). Density functional theory calculations show that the formation of heterostructures reduces the activation energy for Na+ migration and increases the electrical conductivity of the material, which accelerates the ion/electron transfer and improves the reaction kinetics of the VS2/VOx electrode. Heterostructure engineering is one of the most promising modification strategies for transition metal sulfides. Herein, based on the spontaneous hydrolysis‐oxidation coupling reaction of transition metal sulfides in aqueous media, homologous VS2/VOx heterostructure is successfully prepared, which exhibits superior cycling stability and rate properties. This study develops a class of anode materials with great performance for sodium storage.