Study On The Doped PPy And Composite Materials As Electrode Material Of Supercapacitor

Supercapacitor, as a new energy storage component, have the advantages of highpower density, long cycle life, rapid charge-discharge function and non-pollution tothe environment and have a great value and great market potential in electronics,communications, transportation, electricity, industrial energy efficiency, nationaldefense, the modern military and aerospace and many other areas.The key to improve the performance of supercapacitor is to find excellent electrodematerials. Certain researches on carbon materials，metallic oxides and conductingpolymers have been made. The pseudocapacitor’s specific capacitance is tens tohundred times of the electric double layer capacitance at the same apparent area. Thepserdocapacitor also has a stable electrolyte concentration during the process ofcharging and discharging. The hybrid capacitors will overcome the limitations of thetwo kinds of capacitors and has a higher energy density and working voltage toachieve the best performance.Researches on the synthesis, modification and composite materials ofsupercapacitor electrode have been done on this article. The suface morphology of theelectrode materials are observed by SEM, the structure characterization are analyzedby XRD and FTIR, and cyclic voltammetry, Galvanostatic charge-discharge, ACimpedance spectroscopy measurements and cycle life test were carried out to test theperformance of supercapacitors. The main content is as follow:1The Polypyrrole doped with sodium p-toluenesulfonic acid electrode materialswere electrochemical polymerized at low temperature by cyclic voltammetry andwere tested in sulfuric acid solution. The results show that the power density in lowtemperature electrochemical polymerization than that of products obtained at roomtemperature. The most excellent product was the one electrochemical polymerizationat0℃, which has a special capacitace of207.83F/g and an energy density of7.01Wh/kg.2The MnO2-DWCNTs composite was prepared by chemical coprecipitation method in low temperature. The TiO2-DWCNTs nanocomposites were prepared by asol-gel method. An asymmetrical supercapacitor assembled with MnO2-DWCNTs aspositive electrode and TiO2-DWCNTs as negative electrode. It was found that, whenthe mass ratio of positive electrode and negative electrode was1:1, the specificcapacitance of the asymmetrical supercapacitor achieved the highest value of250.71F/g and an energy density of17.36Wh/kg.3The Manganese dioxide (MnO2) and activated carbon (AC) materials areinexpensive and rich-source electrode materials. The nano MnO2was prepared bychemical coprecipitation method in low temperature. The MnO2-AC compositematerial was successfully synthesized by sintering in high temperature through nanoMnO2, glucose and nano silicon oxide (SiO2). The result indicated that the preparedcomposite MnO2-AC has a synergistic effect and smaller size. The specificcapacitance of the symmetrical supercapacitor achieved the highest value of94.43F/gand an energy density of2.73Wh/kg.