Preparation And Electrochemical Application Of ZnCo₂O₄@NiCo₂S₄ Nano Energy Storage Material

In recent years,the research of renewable,low-cost and environmentally friendly energy storage materials has become a hot spot of scientific research,in which super capacitor is one of the most effective and practical electrochemical energy storage and conversion technologies.The hydrothermal synthesis of Zn Co₂O₄,Ni Co₂S₄ and Zn Co₂O₄@Ni Co₂S₄composites was studied.The microstructure and electrochemical properties of the three electrode materials were studied by means of XRD,SEM,CV,GCD and EIS.The effects of raw materials,holding time,heating temperature,concentration of raw materials,molar amount of relative Zn and amount of urea on the micro morphology and electrochemical properties of the composite were studied.Under the optimum synthesis conditions,the mass specific capacitance of Zn Co₂O₄electrode material is 605.9c/g at the current density of 1A/g.after 6000 cycles of charging and discharging,the capacitance retention rate is 75.06%.Ni Co₂O₄ electrode material can be synthesized by hydrothermal method.Because of its spherical structure,the distance between the nanoflakes increases the specific surface area of the nanoflakes.The composite Ni Co₂S₄ electrode has a mass specific capacitance of 744c/g and a current density of 1A/g.after 6000 cycles of charging and discharging,its capacitance retention rate is 78.43%.Zn Co₂O₄@Ni Co₂S₄ composite was prepared by two-step hydrothermal synthesis.According to the electrochemical test,its current density is 1A/g,and the mass specific capacitance of the composite is 1292c/g.after 10000 cycles of charging and discharging,its capacitance still maintains 84.3%.After 10000 cycles of charging and discharging,the super assembled device still maintains 79.5%of the initial unit specific capacitance.