Synthesis and characterization of flower-like MoO3/In2O3 microstructures for highly sensitive ethanol detection

Abstract

Flower-like pure and Mo-loaded In₂O₃ hierarchical microstructures were synthesized by a facile hydrothermal method. The morphology, crystal structures, and compositions of the samples were characterized by SEM, XRD, TEM, showing nanosheets with dimensions of 4 μm diameter and 25 nm thickness. Gas sensing experiments were conducted on the as-prepared MoO₃/In₂O₃ gas sensors, and the results prove that Mo-loaded In₂O₃ gas sensors exhibit enhanced gas sensing properties at 185 °C. In particular, the 3 mol% Mo-loaded In₂O₃ provided a high response (7 to 100 ppm ethanol), fast response and recovery time (11 s and 94 s), low detection limit (50 ppb), good selectivity and stability for ethanol detection, which is promising for low concentration ethanol detection in practical applications.