借助交流阻抗谱测试技术和扫描电镜,对Pt,Au,Ag,Ag—Pt,Ag—Pd电极浆料所制金属/YSZ电极的界面电阻、激活能进行了研究,并计算了由其构成的氧传感器达到90%响应量所需时间。研究表明:400-600℃时,02在Ag/YSZ电极上反应速率最快,激活能最低,为91kJ·mol^-1;Pt/YSZ电极激活能最高,为183kJ·mol^-1,电极反应速率控制步骤为吸附氧原子在电极表面的扩散过程;Ag—Pt,Ag—Pd/YSZ电极激活能均较Ag/vsz电极高,Pd含量增大时,Ag—Pd/YSZ电极激活能亦增大;400-450℃时,Ag/YSZ氧传感器响应时间最短,450-600℃时,Ag-1%Pd/YSZ氧传感器响应最快。
By means of SEM observation and complex AC impedance, the interfarial resistance and activation energy of M/YSZ electrodes (M =Pt,Au,Ag, Ag-Pt, Ag-Pd) are investigated,and the 90 % response time of oxygen sensors made up of these electrodes are calculated. The study indicates that at 400 - 600℃, the Ag,/YSZ electrode has the fastest 02 reaction rate and the lowest activation energy of 91 kJ . mol^-1 ; Pt/YSZ electrode has the highest activation energy of 183 kJ . mol^-1, rate determining step ( RDS ) of the electrode reaction is the diffusion of adsorbed oxygen atoms on the Pt surface towards the YSZ; each of the Ag-Pt/YSZ and Ag-Pd/YSZ electrodes has higher activation energy than the Ag/YSZ electrode, and the activation energy of Ag-Pd/YSZ electrode increases as the content of Pd increased ; Ag,/YSZ oxygen sensor has the shortest response time at 400 - 450 ℃ ,but during 450 -600 ℃ ,it is Ag-1% Pd/YSZ oxygen sensor that has the fastest response rate.