Solvent-Controlled Morphology of Zinc–Cobalt Bimetallic Sulfides for Supercapacitors

作者：Xiaobei Zang, Xiaoqi Tang, Liheng Liang, Xuhui Liu, Xiaobin Zhang, Xingdong Ma, Guoshun Liu, Chao Li, Ning Cao, Qingguo Shao · 发表于：Molecules · 年份：2023 · DOI：10.3390/molecules28186578 · 被引用次数：12 · 研究领域：Supercapacitor Materials and Fabrication、Advanced battery technologies research、Electrocatalysts for Energy Conversion

Bimetallic sulfides offer high theoretical specific capacitance and good stability as electrode materials due to their diverse redox reactions, larger specific surface areas, and better conductivity. The morphology of the electrode material is an important influencing factor for the electrochemical properties. Herein, a series of ZnCoS electrode materials with different morphologies were prepared by varying the solvent in the solvothermal reaction, and the effects of different microstructures on the electrochemical properties of ZnCoS were investigated. The ratio of water and ethanol in the solvent was controlled to modulate the microstructure of the as-prepared ZnCoS materials. XRD and XPS revealed the physical and chemical structure of the ZnCoS materials. SEM and TEM observations showed that the microstructure of ZnCoS transformed from one-dimensional wires to two-dimensional sheets with increasing amounts of ethanol. The maximum specific capacitance of the as-prepared ZnCoS materials is 6.22 F cm−2 at a current density of 5 mA cm−2, which is superior to that of most previously reported bimetallic sulfides. The enhanced electrochemical performance could be ascribed to its sheet-assembled spherical structure, which not only shortens the path of ion diffusion but also increases the contact between surface active sites and the electrolyte. Moreover, the spherical structure provides numerous void spaces for buffering the volume expansion and penetration of the electrolyte, whi...