钌铱及铱钽氧化物涂层钛电极加速寿命及失效原因研究

Study on the Accelerated Life and Failure Analysis of Ruthenium-Iridium Oxides and Iridium-Tantalum Oxides Coated Titanium Electrodes

采用加速寿命试验研究对比RuO_(2)IrO_(2)/Ti及IrO_(2)Ta_(2)O_(5)/Ti两种涂层电极的加速寿命,并研究了水中不同浓度氟离子对这两种电极加速寿命的影响。试验结果表明,IrO_(2)Ta_(2)O_(5)/Ti电极的加速寿命约为RuO_(2)IrO_(2)/Ti电极的加速寿命的40倍。水中氟离子对两种电极加速寿命有明显影响,当氟离子浓度为1 mg/L时,即可使RuO_(2)IrO_(2)/Ti电极的加速寿命下降22%,使IrO_(2)Ta_(2)O_(5)/Ti电极的加速寿命下降82%。氟离子具有很强的渗透性和腐蚀性,会使表面氧化物薄膜脱落,使钛基底暴露于电解液中被氧化成二氧化钛,导致电极完全失效。扫描电子显微镜、能谱分析结果表明,电极催化层中有效成分的溶解、电极催化层的开裂和剥落引起的钛基底暴露和氧化可能是导致电极失效的直接原因。

The accelerated life of RuO_(2)IrO_(2)/Ti and IrO_(2)Ta_(2)O_(5)/Ti was studied and compared,and the effects of fluorine ion on the accelerated life of the two above-mentioned electrodes were studied.Experimental results show that the accelerated life of IrO_(2)Ta_(2)O_(5)/Ti electrode is about 40 times that of RuO_(2)IrO_(2)/Ti electrode.The presence of 1 mg/L fluorine ions can reduce the accelerated electrode life of RuO_(2)IrO_(2)/Ti electrode by 22%and the accelerated electrode life of IrO_(2)Ta_(2)O_(5)/Ti electrode by 82%.The causes of electrode failure were analyzed by scanning electron microscopy and energy spectroscopy.The analysis results show that the dissolution of the active ingredient in the electrode catalytic layer,the cracking and shedding of the electrode catalytic layer caused exposure and oxidation of the substrate could be the direct causes of the electrode failure.