Structure Regulation And Electrochemical Performance Optimization Of Transition Metal Oxides And Sulfides

Transition metal oxides and sulfides are important electrode materials for supercapacitors.The copper-cobalt binary metal oxide has abundant resources,good conductivity,rich oxidation state and high theoretical specific capacity.Molybdenum disulfide material has structural characteristics similar to graphite,and has a microscopic morphology and excellent electrochemical activity similar to graphene.Therefore,this paper carried out a systematic study on the copper-cobalt binary metal oxide and molybdenum disulfide.We use solvothermal method to prepare Cu Co₂O₄/Cu O in ethylene glycol/isopropanol and glycerol/isopropanol mixed solvent.Adjust the amount of NH₄HCO₃ in the ethylene glycol/isopropanol system,and adjust the concentration of metal ions and the amount of surfactant PVP in the glycerol/isopropanol system,to regulate the morphology of Cu Co₂O₄/Cu O.Choose glycerin/isopropanol as the solvent,the ratio of Cu²⁺:Co²⁺is 1:2.5 mmol,and the amount of PVP is 0.1 g,we get microspheres with relatively uniform pore distribution.At 1 A g^-1,the specific capacity is 81.61 m Ah g^-1(587.57 F g^-1),and the specific capacity retention is 80%after 6000cycles at 5 A g^-1.MoS₂ was prepared by solvothermal method in H₂O,DMF,NMP and Et OH.When the solvent is H₂O,we get a flower ball structure formed by lamination.Material provides great specific surface area and more exposed active sites.At 1 A g^-1,the specific capacity is 80.39 m Ah g^-1(578.84 F g^-1).Later,using DMF and H₂O,the in-situ growth of MoS₂ was achieved on the nickel foam,and an integrated electrode was prepared.Nickel foam as a high-speed channel for electron transmission,improves the overall conductivity of the electrode,also enhances mechanical properties by providing structural support.When H₂O is used as a solvent,the 2D characteristics of MoS₂ are maintained.At 1 A g^-1,the specific capacity is 300.26 m Ah g^-1,and the specific capacity retention rate is 73.8%.The specific capacity retention rate was 160%after 4000 cycles at 10 A g^-1.