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测量了钌镧氧化物涂层的电化学阻抗谱（EIS）,结合循环伏安（CV）及扫描电子显微镜形貌分析,研究了钌镧氧化物涂层阳极在3.5%NaCl溶液中电化学表面结构及电化学行为.在非析氯反应区间,该涂层EIS数据的最佳拟合等效电路是Rs（RctQdl）,在析氯反应区间,其等效电路为Rs（RfQf）（RctWQdl）.高频段阻抗行为对应涂层的物理阻抗,低频段对应涂层与溶液界面的电化学反应阻抗.实验结果表明,随着La浓度增加,氧化膜及双电层的伪电容增大,且在La含量30mol%时达到最大值,与CV实验结果一致,证明了加入La能提高RuO2涂层的电催化活性.但在析氯反应区间,涂层氧化膜的导电性在含La大于30 mol%之后迅速下降,在低频段产生Warburg阻抗,与其表面钝化和特性吸附现象有关,这是导致含La 70 mol%时电催化活性急剧下降的原因.“,”Electrochemical surface structure and electrochemical performance of Ti based Ru-La oxide coatings in 3.5% NaCl solution have been investigated by electrochemical impedance spectroscopy（EIS）,together with cyclic voltammetry（CV） and scanning electron microscopy（SEM）.The best-fit circuit to EIS data of the coatings in the absence of the chlorine evolution reaction is Rs（RctQdl）,and that in the potential range of chlorine evolution reaction is Rs（RfQf）（RctWQdl）.The high-frequency region corresponds to the impedance behavior of the coating,and the low-frequency region to that of the interface between outer surface and electrolyte.Results show that the pseudo-capacitances of the oxide film and the double layer increase with increasing La content,reaching a maximum at the nominal La content of 30 mol%.This finding agrees with the CV result,suggesting that the La additive in suitable amount can improve the electrochemical activity of the RuO2 coating.The electric conductivity of the coatings,however,significantly decreases when nominal La content is larger than 30 mol% in the region of the chlorine evolution potential.A character with a Warburg impedance at low-frequency region suggests the relationship to passivation of the coating surface and specific adsorption,resulting in a dramatic decrease of electrocatalytic activity of the coatings at norminal La content of 70 mol%.