Ethanol gas sensor based on tungsten doped In2O3 nanoparticles

Prolonged exposure to ethanol gas in the air can have deleterious effects on the human respiratory system and even pose an explosion risk. Therefore, it is imperative to monitor the concentration of ethanol gas and reliably detect its presence. In this study, tungsten-doped indium oxide (W-In 2 O 3 ) nanocomposites were synthesized by a hydrothermal method and utilized in gas sensors. The microstructures and morphologies of the nanocomposites were examined using various analytical methods, and the results indicated that W-In 2 O 3 was successfully synthesized. For instance, at optimal temperatures (280 °C) the gas-sensitive characteristics of W-In 2 O 3 composites were examined in response to varying ethanol gas concentrations (1−100 ppm). In particular, the sensor with a doping concentration of 10 % provided the best performance, as compared to the pure In 2 O 3 sensor, and displayed the highest response to 100 ppm of ethanol (33.2). Furthermore, this response is approximately 1.5–2 times better than that of pure In 2 O 3 , and simultaneously, in a cyclic test, the sensors consisting of W-In 2 O 3 exhibited excellent selectivity, fast response, short recovery times (10 and 60 s, respectively), good repeatability, and stability. In particular, the shift in microcrystal size caused by W doping was responsible for the notable augmentation of the sensitivity to ethanol, suggesting that the sensor may have potential applications for the detection and monitoring of ethanol gas.