作　　者： ; ; ; ; ; ;

机构地区： 中国科学院地球化学研究所

出　　处： 《功能材料》 2008年第12期1997-2001,2004,共6页

摘　　要： 借助交流阻抗谱测试技术和扫描电镜，研究了Pt／YSZ电极烧制工艺条件对其性能的影响。研究表明，制作Pt／YSZ电极时烧结温度越高，电极阻抗越大，氧传感器响应越慢，但O2的电极还原反应速率控制步骤（〉600℃，吸附氧原子Oatm在Pt表面向YSZ的扩散过程；〈500℃，气相O2分子在Pt／YSZ界面附近的解离吸附过程）未发生变化；电极烧结的升／降温速率对电极阻抗和氧传感器响应时间有显著影响，降温速率增大还会使电极反应激活能发生突变（〉600℃，激活能由169kJ／mol突然增至（217±4）kJ／mol）；当Pt／YSZ电极工作温度〈500℃时，其最优烧制工艺为烧结温度700℃，升／降温速率0．5～1℃／min。 By means of SEM observation and complex AC impedance, the effects of the Pt/YSZ electrode sintering technics on its characteristics were studied. The investigation indicates that the resistance of the electrode increases and the response time of the oxygen sensor decreases as the sintering temperature is lowered, but the rate determining step（RDS） of the O2/O^2- electrode reaction remains unchanged （above 600℃, the diffusion of adsorbed oxygen atoms on the Pt surface towards the YSZ; below 500℃, the dissociative adsorption of oxygen molecules on the Pt surface near the Pt/YSZ boundary） heating/cooling rate affects the interracial resistance of the Pt/YSZ electrode and the response time of the oxygen sensor badly, the increase of cooling rate can even give a sudden change to the activation energy of the electrode reaction （above 600℃,the activation energy increases from 169kJ/mol to （217±4）kJ/mol suddenly） Pt/YSZ electrode has its best sintering technics when it operates below 500℃, the best sintering temperature and heating/cooling rate are 700℃ and 0.5-1℃/min respectively.

关 键 词： 电极 阻抗谱 烧结温度 升 降温速率

领　　域： [化学工程] [化学工程]