Synthesis, characterizations and gas sensing properties of nanocrystalline In2O3 thick film sensor

The nanocrystalline powder of In 2 O 3 with cubic structure prepared by a simple hydrothermal decomposition route. The structure and crystal phase of the powder was characterized by X-ray diffraction (XRD), microstructure by Transmission Electron Microscopy (TEM). The results indicated that the indium oxide was cubic with range size 28.5- 65.8 nm. Gas sensing properties of the nanocrystalline In 2 O 3 thick film sensor were tested for various gases in air at static state. The tested results showed that the sensor based on In 2 O 3 nanocrystals exhibited high response towards H 2 S gas (40 ppm) at an operating temperature 100°C. The selectivity of the sensor elements for H 2 S gas against different gases was studied. The results on response and recovery time were also discussed.