Influence of Structure of Fe2O3−In2O3 Nanocomposites on the Sensitivity of Thin-Film Sensors on their Base

Abstract

Thin-film sensing layers based on Fe2O3eIn2O3 nanocomposites with different component ratio and structural features were synthesized by inorganic modification of solegel method. The phase composition and morphology of the composites as a function of the synthesis conditions were studied by X-ray diffraction, transmission electron microscopy, electron diffraction, differential scanning calorimetry, electron paramagnetic resonance and infrared spectroscopy. The gas-sensing parameters the Fe2O3 eIn2O3 composites were correlated with their structure. The synthesis conditions resulting in the formation in the Fe2O3eIn2O3 composites of metastable g-Fe2O3 phase, which is characterized by an enhanced activity in adsorption and catalysis as compared to a-Fe2O3 oxide, were revealed. An improved sensitivity of g-Fe2O3 based composites to different gases was shown. The chemical and structural compositions of Fe2O3eIn2O3 thin-film sensing layers and operating temperatures optimal for the detection of O3, NO2 and C2H5OH were proposed.