Metal oxide semiconductors based on tin dioxide: Gas-sensitivity to methane in a wide range of temperatures,concentrations and humidities of the gas phase

The response of metal oxide semiconductors (MOSs) made by the thick-film technology on the basis of SnO₂ with various catalytic additives was studied in dry gaseous media containing 200 ppm CH₄ in the temperature range 100–600° C. Concentration dependence was studied for four sensors (on the basis of pure SnO₂ and with three catalytic additives, 3% Pd, 1% Sb₂O₅ + 3% La₂O₃, and 1% Pt + 3% Pd) in the concentration range 1–20600 ppm CH₄ at the humidity of the gas phase varied from 0 to 100%. It was found out that, in the strength of all performance and technical characteristics, the structure SnO₂ + 1% Pt + 3% Pd working at 400°C and consuming ～180 mW was the best for recording CH₄.