P1NM.12 - Au-decorated ZnO Nanowires for Selective Ethanol Sensing

17th International Meeting on Chemical Sensors - IMCS 2018
2018-07-15 - 2018-07-19
Vienna, Austria
P-1 - Nanomaterials
S. Singkammo, C. Liewhiran, S. Phanichphant - Chiang Mai University, Chiang Mai (Thailand), A. Wisitsoraat - National Science and Technology Development Agency, Klong Luang, Pathumthani (Thailand), D. Zappa, A. Ponzoni, G. Sberveglieri, E. Comini - University of Brescia, Brescia (Italy)
601 - 602


Metal oxide semiconductors based on 1-D nanostructures such as nanorod, nanobelt and nanowire are promising candidates for gas sensing application due to high surface area to volume ratio [1]. ZnO is one of most promising metal oxides, it has a wide band gap (3.37 eV) and applies for gas sensing application [2]. In this work, ZnO nanowires were grown with vapor-liquid-solid (VLS) mechanism via thermal evaporation-condensation method using Au catalyst for structural evolution [1, 3, 4]. Particularly, the as-prepared ZnO sensing films were functionalized with Au catalyst by varying the sputtering time ranging from 0-15 s. The choice of Au catalyst comes from its important role in significant enhancement the gas-sensing properties. For the sensing results, all sensors were systematically studied towards NO2, NH3, C3H6O and CO, C2H5OH with different working temperature ranging from 250 to 400 °C in dry and wet air. Nanowires functionalized with Au sputtering time at 5 s led to the highest response of 80.7 toward 70 ppm C2H5OH, which was higher than that of bare ZnO nanowire sensor (S=2.16) and those of the other gases at the optimal working temperature of 350°C with 30% humidity. Therefore, the sensor is a promising candidate as a sensitive and selective ethanol detector corresponding to threshold limit value and practical humidity effect for ethanol-sensing applications.