A novel catalytic sensor for monitoring the concentration of mixed combustible gases

This paper studies gas detectors, especially, gas sensors in which a thermochemical reaction takes place on a catalytic element. The novel catalytic sensor is fabricated using microelectronic thick-film techniques, and it is used to monitor the concentration of combustible gases and their mixture in a flow reactor. This sensor has two identical platinum films which are used as the heater, resistance thermometer and the surface of reaction. Catalyst of palladium is deposited on one of the platinum film by chemical method, while the other platinum film serves as a compensating element. The difference in the minimum reaction temperature for the catalytic oxidation of the combustible gas components of mixture by palladium suggests that it is possible to analyse such a gas mixture. The purpose of the study is to demonstrate that the sensor fabricated by this process has good sensing characteristics for hydrogen or carbon monoxide gas in the mixture of methane and ethane.