Structure Regulation And Electrochemical Performance Of Supercapacitor Electrode Materials Based On CuCo₂S₄

Transition metal sulfides possess high theoretical capacity as supercapacitor electrode materials,but their poor conductivity makes the practical electrochemical performance lower than theoretical value.In this paper,materials based on CuCo₂S₄are designed and fabricated to improve the electrochemical performance by controlling hollow structure,preparing integrated electrode,constructing multiphase composite electrode,result in electrodes and devices with high specific capacity and long cycle life.Effects caused by sulfur powder,thioacetamide and thiourea to the hydrothermal synthesis of CuCo₂S₄ were studied in this paper and CuCo₂S₄ with hollow spheres structure were obtained by the bubbles generated from thioacetamide and thiourea in the hydrothermal process.The mechanism of the bubbles generation rate on the in-situ self-assembly the hierarchical structure on the surface have been studied,and the mechanism of how different microstructures affect the electrochemical performance of the CuCo₂S₄ electrode have also been studied.The hierarchical CuCo₂S₄ hollow spheres have the best electrochemical performance,and the capacity retention rate is as high as 94.9%after 6 000 cycles at 5 A g^-1.Integrated electrode was constructed by in-situ growth of CuCo₂S₄ on Ni Foam,the microstructures and structural characteristics of the integrated electrode were characterized by different ratio of raw materials,different reaction temperature and different reaction time,and the effect of different microstructures on the performance of integrated electrodes was studied.The CuCo₂S₄ nanoneedle array grown on the Ni Foam can provide short ion-transport pathways for electrons and ions,and the Ni Foam can increase the ion diffusion rate in the electrolyte,so the integrated electrode exhibits excellent electrochemical performance.Ni?OH?₂ was grown on the integrated electrode of CuCo₂S₄/Ni Foam by electrochemical deposition and constructing integrated electrode of multiphase composite,and the influence mechanism of different electrodeposition time on microstructure and properties was studied.The hybrid supercapacitor assembled with the composite electrode possess excellent performance with 39.7 Wh kg^-1 and power density up to 5840 W kg^-1,providing outstanding stability performance with 87.9%after 5000 cycles at 6 A g^-1.