Comparative study of various metal-oxide-based gas-sensor architectures
(EN)
Papadopoulos, CA
(EN)
Avaritsiotis, JN
(EN)
Vlachos, DS
(EN)
Reactively sputtered SnOx and InOx thin films, plain and surface doped with Pt, have been covered with layers of various insulating films and catalysts. Test gases used are carbon monoxide, methane, ethanol, butane and propane. Filters used are alumina (Al2O3), silicon oxide (SiO2) and tungsten trioxide (WO3). Palladium has also been added on the surface of alumina filters, while platinum is added on the surface of metal-oxide sensor films. Response to hydrocarbons, and especially to butane and propane is found to be enhanced with the addition of noble metals on the sensing film or on the filter. It is also found that a WO3 filter improves the carbon monoxide sensitivity at low working temperatures and reduces the sensor response to ethanol with respect to other test gases. The behaviour of indium-oxide-based sensors is qualitatively very similar to that of tin-oxide-based sensors.
(EN)
