Preparation Of Composites Based On Porous CuO-Cu₂O Microspheres And Study Of Their Electrochemical Performance

With the rapid development of society,coal,petroleum and other traditional non-renewable fuels have been extensively consumed.Energy shortage and environmental damage have limited economic development to a certain extent.Therefore,the vigorous development of new energy is imminent,and the development of energy storage devices is an important condition for the storage and efficient use of new energy.Among them,the supercapacitor has become a research hotspot and focus because of its advantages of high-power density,fast and safe charging,long service life,and environmental protection.At present,the main problem in the application of supercapacitors is the low energy density,and one of the main factors determining the energy density is the choice of electrode materials and the control of their morphology and structure.Copper oxides?CuO,Cu₂O?are common pseudo-supercapacitor electrode materials,which have the advantages of low cost,abundant resources,environmentally friendly and high theoretical specific capacitance.The two-component CuO-Cu₂O composite material can undergo a highly reversible redox reaction between Cu⁺and Cu²⁺,so this material has more excellent electrochemical performance.In addition,as electrode materials,the porous microsphere-like structure and morphology have higher specific surface area and shorter ion transport path than sheet-like materials,which provides an effective way for better contact between electrode materials and electrolyte and faster ion transmission.Therefore,in this paper,the porous CuO-Cu₂O microsphere material can be controlled and further compounded with graphene and molybdenum disulfide?Mo S₂?to prepare electrode materials with excellent electrochemical performance.1. The porous CuO-Cu₂O microsphere material was successfully prepared by one-step hydrothermal method,controlling the variables to change the reaction time and reaction temperature.The test results display that the porous CuO-Cu₂O microsphere material has more excellent electrochemical performance than other structures of CuO-Cu₂O material.2. On the basis of the first work,solid and hollow CuO-Cu₂O/graphene?rGO?composite microspheres were prepared by hydrothermal method and their electrochemical properties were studied.The results show that the hollow-structured CuO-Cu₂O/rGO electrode material is more excellent.In addition,we studied the effect of the amount of graphene oxide on the ratio of CuO to Cu₂O,and could control the CuO-Cu₂O/rGO composite electrode material with the best electrochemical performance.3. Cu₂O-Cu₂S/rGO composite material was successfully prepared after partial vulcanization of Cu₂O-Cu₂O/rGO composite material.The electrochemical test results show that partial vulcanization of Cu₂O-Cu₂O/rGO not only effectively improves the specific capacitance of the material,but also further improves its cycle performance.4. Using the porous CuO-Cu₂O microspheres as templates,the porous Cu S-Mo S₂ microsphere composite material was synthesized by sacrificial template method.The experimental results show that under the synergy of the two materials and good structural construction conditions,the Cu S-Mo S₂ composite material exhibits excellent electrochemical performance,especially the rate characteristics are significantly improved.