Highly Improved Ethanol Gas Sensor Sensitivity, Selectivity, and Stability of Hierarchically Cube Featured In2O3 Structures Induced by Mn- and Co-Doping

Herein, we report a rapid detection of ethanol of hierarchically featured cube In₂O₃ structures induced by Mn and Co derived from hydrothermal approach. Systematic investigation and comparison of the structural, morphological, and textural features of undoped, Mn, and Co–In₂O₃ were probed to gain more understanding about their gas sensing performance. A sensor based on 1 mol% Mn-doped In₂O₃ demonstrated enhanced ethanol gas sensing characteristics with a response of 35.5 toward 50 ppm of ethanol at minimal working temperature of 80 °C, good selectivity along with quick response/recovery times of 7/161 s. The excellent gas sensing results stem from the particle-interlinked nanocubes resembled by 3-D hierarchical features, which endowed large content of reactive sites for the adsorption of ethanol gas due to high surface area and mesoporous features, which permitted ethanol gas molecules diffusion in/out of the active sensing layer.