Improved Toluene Response of Mixed-Potential Type YSZ-Based Gas Sensors Using CeO<sub>2</sub>-Added Au Electrodes
Improved Toluene Response of Mixed-Potential Type YSZ-Based Gas Sensors Using CeO<sub>2</sub>-Added Au Electrodes
复制标题
使用添加 CeO<sub>2</sub> 的 Au 电极改善混合电位型 YSZ 基气体传感器的甲苯响应
DOI：
10.1149/2754-2726/ac63d2
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Shimizu Yasuhiro
中科院分区：
文献类型：
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作者：
Ueda Taro;Oide Nobumitsu;Kamada Kai;Hyodo Takeo;Shimizu Yasuhiro
采用旋涂法制备了以YSZ为基体的Au敏感电极，研究了CeO 2的添加对甲苯敏感性能的影响.添加8wt%CeO2的Au SE的传感器对50 ppm甲苯的响应（ΔE）随着旋涂循环次数（x：5，10，15;即SE的厚度）的增加而趋于降低。然而，使用24wt%CeO2添加的Au SE的传感器的ΔE表现出与观察到的8wt%CeO2添加的Au SE相反的行为。使用最厚SE（x：15）的传感器显示最大ΔE（例如，约212 mV（对于50 ppm甲苯），在所有检测的传感器中，甚至对0.5 ppm甲苯也有响应。在大于10 ppm的范围内，ΔE随甲苯浓度对数的增加呈指数增加。这些结果表明，甲苯的电化学氧化除了在SE/YSZ/gas的传统界面上进行外，还在SE中与气体（Au/CeO 2/gas）和传统TPB（SE/YSZ/gas）的三相界面上进行，因为CeO 2是一种混合的离子和电子导体。根据I-E特性和电化学阻抗特性，讨论了传感器TPB处的电化学反应。
YSZ-based potentiometric sensors employing thin CeO 2-added Au sensing electrodes (SEs) were fabricated by using a spin-coating method, and effects of the CeO 2 addition on their toluene sensing properties were examined. The sensor response (ΔE) to 50 ppm toluene of the sensors using 8 wt% CeO 2-added Au SEs tended to decrease with an increase in the number of spin-coating cycles (x: 5, 10, 15; ie, the thickness of SEs). However, ΔE of the sensors using 24 wt% CeO 2-added Au SEs showed an opposite behavior to what was observed for 8 wt% CeO 2-added Au SEs. The sensor using the thickest SE (x: 15) showed the largest ΔE (eg, ca. 212 mV for 50 ppm toluene) at 450 C among all the sensors examined and responded even to 0.5 ppm toluene. ΔE exponentially increased with an increase in logarithmic toluene concentration in the range higher than 10 ppm. These obtained results indicate that electrochemical toluene oxidation proceeds at triple-phase boundaries in SE with gas (Au/CeO 2/gas) in addition to conventional TPBs (SE/YSZ/gas) in addition to the conventional interface at SE/YSZ/gas, because CeO 2 is a mixed ionic and electronic conductor. The electrochemical reactions at TPBs of the sensor were also discussed on the basis of the I–E characteristics and the electrochemical impedance properties.