IrO2涂覆载量对IrO2-CeO2-G/Ti电极组织结构和电容性能的影响

Effect of IrO2 Content on Microstructure and Capacitance of IrO2-CeO2-G/Ti Electrode

采用热分解法制备了新型IrO2-CeO2-G/Ti复合电极。采用SEM、TEM、XRD和XPS等测试手段分别对不同IrO2含量的电极进行表征。采用循环伏安法、恒流充放电法和电化学阻抗谱法对电极的电化学行为进行研究。结果表明,IrO2涂覆载量为2.5 mg/cm2的电极具有最大的比电容值459.5 F/g。在5 mA/cm2电流密度下,经5000次充放电循环后IrO2涂覆载量为2.5 mg/cm2电极比电容仍能保持97.8%。该种复合电极材料因其独特的元素组成和良好的赝电容性能,是一种理想的超级电容器电极材料。

The novel IrO2-CeO2-G/Ti composite electrodes were prepared by thermal decomposition method.The synthesized electrodes with different IrO2 content were characterized by scanning electron microscope(SEM),transmission electron microscope(TEM),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).The electrochemical performances of the electrodes were investigated by cyclic voltammetry,galvanostatic charge–discharge and electrochemical impedance spectroscopy in 0.5 mol/L H2SO4 solution.The results show that the electrode with 2.5 mg/cm2 IrO2 exhibits an excellent specific capacitance value of 459.5 F/g,and maintains the specific capacitance at about 97.8%after 5000 charge-discharge cycles at 5 mA/cm2 current density.The electrode with 2.5 mg/cm2 IrO2 is an ideal electrode for supercapacitor due to its unique composition proportion and the excellent pseudocapacitance property.