Structural and sensing properties of Sb2O3-SnO2 thick film

The present work deals with the study of the structural and sensing behavior of Sb2O3-doped tin oxide thick film. Three kinds of sensors undoped SnO2, 5 wt% Sb2O3-SnO2, and 15 wt% Sb2O3 doped-SnO2 are prepared by screen-printed on designed alumina substrate. The structural properties of fabricated sensors are analyzed by using XRD and their sensing behaviors were examined for ethanol gas. The XRD measurement reveals that the average crystallite size of undoped SnO2 and doped SnO2 with Sb2O3 composition i.e., 5 wt% Sb2O3-doped SnO2 and 15 wt% Sb2O3-doped SnO2 is 28.83 nm, 21.61 nm, and 18.53 nm respectively. The addition of Sb2O3 content in SnO2 reduces the crystallite size and thus, Sb2O3 doping suppresses SnO2 crystallite growth. The response of the fabricated sensor is measured with the varying concentration of the ethanol (0-5000 ppm) in the testing chamber at the different operating temperatures of 150 degrees C, 200 degrees C, and 250 degrees C. We observed that Sb2O3 doping improved response and the 15 wt% antimony oxide doped sample showed a maximum response of similar to 73.5% for ethanol gas (5000 ppm) at 250 degrees C. The experimental result for ethanol gas has been validated with the theoretical model and observed results are found to be in good agreement with that proposed model.