Abstract Pristine and Ag-added (1.5, 3.5 and 5.5 wt%) ZnO nanoparticles (NPs) were synthesized by a Pechini sol-gel route for evaluation of their gas sensing properties. The samples were fully characterized by different characterization techniques. Based on the sensing results obtained in this study, the promising effects of Ag on the ethanol vapor response of ZnO were demonstrated. In particular, the optimized sensor, namely 3.5 wt % Ag-ZnO gas sensor exhibited a response (Ra/Rg) of 32.5 to 50 ppm ethanol vapor at 325°C. A second notable finding revealed that this optimized sensor had a better selectivity to the ethanol vapor relative to the pristine ZnO gas sensor. The sensing mechanism was associated with the catalytic effect of Ag, the formation of Ag-ZnO heterojunctions and the basic characteristics of ZnO. This work highlights the importance of a systematic study for adding noble metals in gas sensing researches.

中文翻译：

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Ag对作为乙醇蒸汽传感器的ZnO纳米颗粒性能的影响

摘要 通过 Pechini 溶胶-凝胶途径合成了原始和添加银 (1.5、3.5 和 5.5 wt%) 的 ZnO 纳米粒子 (NPs) 以评估其气敏特性。通过不同的表征技术对样品进行了全面表征。基于本研究中获得的传感结果，证明了 Ag 对 ZnO 的乙醇蒸汽响应的有希望的影响。特别是，优化的传感器，即 3.5 wt% Ag-ZnO 气体传感器在 325°C 下表现出 32.5 至 50 ppm 乙醇蒸汽的响应 (Ra/Rg)。第二个值得注意的发现表明，与原始 ZnO 气体传感器相比，这种优化的传感器对乙醇蒸汽具有更好的选择性。传感机制与Ag的催化作用、Ag-ZnO异质结的形成和ZnO的基本特性有关。