Facile green synthesis of In2O3 bricks and its NO2 gas sensing properties

Abstract

Recently, metal oxide semiconductor based gas sensors have been used to monitor and maintain amount of toxic gases in environment. Use of In2O3 nano/microstructures have been increased as a heterogeneous catalyst for gas sensing due to its high response, good selectivity, short response and recovery time. In the present work, synthesis of In2O3 bricks was carried by a hydrothermal method using biomolecule as green product. The effect of precursor concentrations of In2O3 thin film was studied in this particular work. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Photoluminescence (PL), scanning electron microscope (SEM), Field emission scanning electron microscope (FE-SEM) and Brunauer–Emmett–Teller (BET) analyses were used for structural, optical, morphological and surface analysis characterizations. The In2O3 thin film displays high sensitivity and selectivity due to its active sites present on sensing layer. The results assures that optimized In2O3 thin films exhibit a high response with very low response and recovery time about 600 for NO2 gas.