On optimum composition of platinum-doped stannic oxide as an active element for methane sensing in air via sensitivity measurements

Abstract

Samples of platinum-doped stannic oxide were prepared by dry pressing method and sintered at 1000 °C for 1 hour, at heating rate of 20 °C per minute, served as an active element in a gas sensor for detecting methane in air. The sensitivity of the gas sensor was measured for samples at nominal dopant levels, 0 – 1 wt% platinum in stannic oxide at an operating temperatures 250 – 400 °C, at a flow rate of 400 sccm with methane in air concentration of 25000 ppm. At an operating temperature of 400 °C, the sensitivity measurements recorded a maximum value of ~1578 at 0.5 wt% Pt in stannic oxide. Therefore we consider 0.5 wt% Pt in stannic oxide as the optimum composition while operating 400 °C as optimum operating temperature.