Preparation And Supercapacitor Properties Of Three Dimensional MnO₂ And Co₃O₄ Electrode

Supercapacitors?or electrochemical capacitors?can bridge function for the power/energy gap between traditional dielectric capacitors?have high power output?and batteries/fuel cells?have high energy storage?,which make supercapacitors can be used in a variety of emerging energy applications.There are three kinds of active materials are used in supercapacitors:carbon,conducting polymers and metal oxides.Among these active materials,metal oxide has became hot spot in the fields of supercapacitor,because of high theoretical specific capacitance,low-cost,environmentally friendly,non-pollution,non-toxic,large potential window.In this paper,we summarized the properties,applications and preparation methods of MnO₂ and Co₃O₄ materials.The three dimensional MnO₂ nanocomposite electrode was prepared by electrodeposition methods.In addition,different morphologies of Co₃O₄ electrodes were obtained by hydrothermal method.The crystal structure and morphology of the materials were analyzed by using a variety of materials test methods.The electrochemistry capacitive performance of the materials was investigated by electrochemistry test methods,the application of the electrodes as asymmetric supercapacitor was systematic studied at the same time.The main details are as follows:1.The NF/CNT/Au/MnO₂ three dimensional composite electrodes were prepared by anodic deposition method for supercapacitor application.Its electrochemical properties were investigated in[Bmim]PF6/DMF electrolyte and different volume fractions were explored.Asymmetric supercapacitors with NF/CNT/Au/MnO₂ electrode as positive electrode and AC as negative electrode were fabricated.2.Different surfactants are used in a typical hydrothermal process for controlling the morphology of Co₃O₄ nanowire superstructure on Ni foam.The electrochemical performances of different Co₃O₄ electrodes were investigated.Asymmetric supercapacitors with Co₃O₄ electrode as positive electrode and AC as negative electrode were fabricated.3.The Co₃O₄/MnO₂ composite electrodes was prepared by anodic deposition method.And the effect of different solution concentrations and different amount of electrodeposited charge were investigated in detail.Button-asymmetric supercapacitors with Co304/Mn02 electrode as positive electrode and AC as negative electrode were fabricated.