Accurate Modulation of Mass Ratio on Electrodes of Ruthenium Oxide//Polyaniline Supercapacitor for Improving Energy Density

Polyaniline and ruthenium oxide electrodes are prepared to assemble the supercapacitors. The electrochemical properties of the electrodes are studied by cyclic voltammetry and galvanostatic charging/discharging measurements. The potential dependence of specific capacitance for the electrodes in the supercapacitors is established. Based on the relationship between specific capacitance and potential of electrodes, the optimum mass ratio of the electrodes in asymmetric supercapacitor of ruthenium oxide//polyaniline can be accurately determined. The working voltage window for ruthenium oxide//polyaniline supercapacitor is significantly increased by the modulation of mass ratio. Accordingly, the electrical energy density of supercapacitor with a mass ratio of = 0.79 is as high as 7.25 Wh kg−1, about 314% higher than that of the supercapacitor with a mass ratio of 0.26.