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用交流阻抗方法研究了Ｌａ０．８Ｓｒ０．２ＭｎＯ３（ＬＳＭ）电极上进行的氧电化学还原反应．实验表明反应速度控制步骤（ｒｄｓ）随反应温度、氧分压及过电位发生显著变化．近平衡下反应的ｒｄｓ为氧的解离吸附过程．强阳极极化下，电解质表面产生大量电子空穴；强阴极极化下，ＬＳＭ电极表面形成大量氧空位，二者的结果均使界面电导增加，电化学反应区扩展．低温强极化及高温强阳极极化下反应的ｒｄｓ为氧的电荷转移过程，高温强阴极极化下为氧的表面扩散过程
The electrochemical reaction of oxygen on La0.8Sr0.2MnO3 (LSM) electrode was studied by AC impedance method. Experiments show that the reaction rate control step (rds) significantly changes with the reaction temperature, partial pressure of oxygen and overpotential. Near equilibrium rds reaction for the oxygen dissociative adsorption process. Strong anodic polarization, the electrolyte surface produces a large number of electron holes; strong cathode polarization, LSM electrode surface to form a large number of oxygen vacancies, the results of both the interface conductivity increases, the electrochemical reaction zone expansion. Rds is the charge transfer process of oxygen at high temperature and strong anodic polarization, and the surface diffusion of oxygen under high temperature and high cathodic polarization