Pure and Cupricated BaSnO3 thick film resistor: Synthesis, Characterization and studies on its gas sensing performance

In this work we report the synthesis, microstructure, electric properties and sensing performance of BaSnO3 (BS) powder, it was prepared by mechano-chemical method. As prepared powder is calcinated at temperatures 1100 o C, and 1300 o C tested for crystallization. Thick films were prepared using simple screen-printing technology. Structural and electrical analyses were performed and the results have been correlated. The material was tested for various gases such as CO, CO2, NH3, Cl2, H2, LPG, ethanol, and H2S. The pure BS film shows good response multiple gases at various operating temperature up to 500 0 C as NH3, CO2, CO, ethanol and, H2S for different gas concentrations, when the pure film is surface modified with aqueous solution of Cucl2 using simple dipping technique for various time intervals (5 min., 10 min., 20 min. and, 30 min.), film improves the selectivity and sensitivity. Maximum response (S=36.2) was found to H2S gas at temperature of 250 0 C and S=12.1 for ethanol at 500 o C for gas concentration of 50 ppm with film dipped for 10 min. time interval. The characterization of the films was done by XRD, SEM and TG-DTA. Crystallite size, texture coefficient, specific surface area, electric properties and gas sensitivity of the films were measured and presented.