Ethanol Sensing Properties of a Gold Nanoparticle/Indium Gallium Oxide Sensor

The ethanol (C 2 H 5 OH) gas sensing properties of a new and novel sensor composed of gold nanoparticles (Au NPs) and an indium gallium oxide (IGO) thin film are comprehensively studied. Au NPs and IGO thin film are synthesized using the vacuum thermal evaporation (VTE) and radio-frequency (RF) sputtering, respectively, and both are treated with a rapid thermal annealing (RTA) approach. The utilization of Au NPs significantly enhances the surface roughness and catalysis effectiveness and then elevates the real sensing performance. The intrinsic properties of Au NPs and IGO thin film are characterized by reasonable analyses. Experimentally, a significant detecting response of 321.2 along with a response (recovery) time of 33 s (20 s) at 1000 ppm of ethanol gas is obtained at 300 °C. Additionally, a lower concentration of 1 ppm C 2 H 5 OH/air can be detected at 300 °C. The related ethanol sensing mechanism of the reported sensor is studied in this work. The proposed Au NP/IGO sensor demonstrates outstanding reproducibility, selectivity, and long-term durability for ethanol gas detection. The produced sensor also exhibits several advantages, including a straightforward sensor structure, ease of fabrication, and cost effectiveness.