应用乙炔黑直接还原高锰酸钾制备MnO2/C复合材料.样品结构及性能由XRD和SEM表征.研究了MnO2/C电极(正极)在不同电解液中的法拉第"准电容行为",及其循环伏安、交流阻抗与恒电流充放电等性能.实验表明,MnO2/C复合材料具有良好的电化学电容特性.在1 mol/L的KOH电解液中和电流密度为5 mA/cm2下,MnO2/C复合材料的比电容量可达258 F/g,并表现出良好的循环性能.
The MnO2/C composite was synthesized by reduction of KMnO4 with acetylene black.The products were characterized by XRD and SEM.We used MnO2/C composite as the positive electrode material of the electrochemical capacitor.The performance of faradic psedocapacitance of the MnO2/C electrode was studied in different electrolytes.The MnO2/C electrode was tested by cyclic voltammetry,electrochemical impedance spectroscopy(EIS) and constant charge-discharge curves.The experimental results showed that the MnO2/C composite has excellent performance.The specific capacitance of the MnO2/C composite as 258 F/g is obtained at 5mA/cm2 current density in 1mol/L KOH solution.It exhibited high discharge capacity and good cycle performance.
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