Preparation Of Bimetal Oxide Electrode Material And Analysis Of Its Electrochemical Performance

Supercapacitors have the energy density and power density between traditional capacitors and fuel cells,as well as the advantages of safety,reliability,environmental friendliness,wide application range and high theoretical capacity,and have received widespread attention.Supercapacitors are composed of current collectors,electrode materials,diaphragms,and electrolytes.The electrode materials have different effects on the overall performance of the supercapacitors because of the vast differences in morphology and composition.At present,research on electrode materials of supercapacitors mainly focuses on carbon materials,transition metal oxides/sulfides/hydroxides and conductive polymers.Among them,transition metal oxides have been extensively studied by scientific researchers because of their high theoretical capacity and rich structural morphology.Binary transition metal oxide has two kinds of metal particles,which can provide more valence to participate in the energy storage reaction,and they can exert the advantages of synergistic effect,making the binary transition metal oxide electrode material display great application potential in supercapacitors.In addition,combining two different materials to prepare composite electrode materials is also a research hotspot,which can give full play to the respective advantages of the two materials and improve the overall electrochemical performance of the materials.This article is based on the above two points to carry out related work:1.ZnCo₂O₄ nanomaterials were prepared by hydrothermal method,and the influence of hydrothermal time on the morphology and electrochemical performance of electrode materials was studied in detail.Studies have shown that when the hydrothermal time is 6 hours,ZnCo₂O₄ has the best morphology and electrochemical performance,with a specific capacitance of 1005F/g at a current density of 1A/g,and a capacitance retention rate of 83.6%after 5000 cycles.The assembled asymmetric supercapacitor ZnCo₂O₄//AC obtained the optimal energy density of 37.5Wh/kg.2.On this basis,Co Se and ZnCo₂O₄ were introduced to recombine,and ZnCo₂O₄@Co Se/NF electrode materials with a layered composite structure were prepared by hydrothermal and electrodeposition methods.This material obtains a specific capacitance of 1684.2F/g at a current density of 1A/g,and the capacitance retention rate is 85.3%after 5000 cycles,which is better than other materials of the same type.The assembled ZnCo₂O₄@Co Se/NF//AC asymmetric capacitor obtained a high power density of 58.44 W/Kg（energy density is 863.32 Wh/Kg）and a high energy density of 7524.83 Wh/Kg（power density is 31.56 W/Kg）.After 5000 cycles,it still has a capacitance retention rate of 84.4%.3.FeCo₂O₄@Co Se/NF electrode material with layered composite structure was prepared by hydrothermal method and electrodeposition method.This material has an excellent specific capacitance of 1448.4F/g at a current density of 1A/g,and has a capacitance retention rate of 94.1%even after 5000 cycles.The assembled FeCo₂O₄@Co Se/NF//AC asymmetric capacitors also obtained a high energy density of57.19Wh/kg（power density is 750W/kg）and a high power density of 7500W/kg（energy density is 27.57Wh/kg）.The capacitance retention rate was 88.7% after 5000 cycles.