Effect of firing temperature on gas sensing properties of nanocrystalline perovskite BaTiO3 thin films prepared by spray pyrolysis techniques

In the present work the spray pyrolysis techniques was employed to prepare nanostructured perovskite BaTiO3 thin films. 0.05 M of Barium chloride (BaCl2·6H2O, 99.9% pure, Merck made, Germany) and 0.05 M Titanium chloride (TiCl3· 6H2O, 99.9% pure, Merck made, Germany) were mixed in the proportion of (30:70%, v/v), (50:50%, v/v) and (70:30%, v/v) respectively. The solutions were sprayed on quartz substrate heated at 350 °C temperature to obtain the films. These thin films were fired in air at temperatures 600 °C and 1000 °C for 2 h. As prepared thin films were characterized using XRD, FE-SEM, EDAX and TEM. The grain size was observed to increase with the increase in firing temperature. To study the effect of firing on structural, microstructural and gas sensing properties of perovskite BaTiO3 thin films. The electrical and gas sensing properties of these films were investigated. The film fired at 1000 °C showed better response to Liquid Petroleum Gas (LPG) as compared to film fired at 600 °C. Gas response, selectivity, response and recovery time of the sensor were measured and presented.