采用循环伏安和电化学阻抗谱等电化学方法对金属氧化物阳极在硫酸中的寿命加速过程进行了监测.检测了阳极伏安电量,双电层电容,氧化物膜电阻和析氧反应的电荷传递电阻等电化学参数随电解时间的变化,并提出金属氧化物阳极电解失效的机理.
The process of accelerated life test of an IrO2/Ta2O5 coated titanium anode was monitored using cyclic voltammetry and electrochemical impedance spectroscopy.The vatiation with electrolysis time of anodic voltammetric charge Q*,the double layer capacitance Cdl,the oxide film resistance Rf and the charge transfer resistance Rct for oxygen evolution was measured.A deactivation mechanism was proposed based on the observation results.
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