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用线性极化、循环伏安、电位阶跃等方法详细研究了La0.8Sr0.2MnO3／YSZ高温电极上进行的氧电化学还原反应．实验结果表明，该反应存在两条路径：低温下氧还原反应主要发生在气相-LSM电极-YSZ电解质接触的三相界面（TPB），速度控制步骤为氧原子在LSM表面的浓差扩散，高温下由于氧空位在LSM表面的形成，氧还原反应区扩展至LSM电极表面，速度控制步骤为氧的电荷转移反应．实验同时发现：氧空位的形成受反应温度、氧分压及阴极电位的影响，氧空位在高温及高氧分压下对反应贡献很大．
The electrochemical reduction of oxygen on La0.8Sr0.2MnO3 / YSZ high temperature electrode was studied in detail by means of linear polarization, cyclic voltammetry and potential steps. The experimental results show that there are two paths for the reaction: the oxygen reduction reaction occurs mainly at the gas-LSM electrode -YSZ electrolyte contact three-phase interface (TPB) at low temperature, the speed control step is concentration diffusion of oxygen atoms on the LSM surface, Due to the formation of oxygen vacancies on the LSM surface, the oxygen reduction reaction zone extends to the surface of the LSM electrode and the rate control step is the charge transfer reaction of oxygen. The experiment also found that the formation of oxygen vacancy is affected by reaction temperature, oxygen partial pressure and cathodic potential. The oxygen vacancy contributes greatly to the reaction under high temperature and high partial pressure of oxygen.