The objective of this research project is to determine the feasibility of detecting combustible gases at elevated temperatures directly from the change in work function of a thin metal film. A broad spectrum of environmentally important inorganic and organic species have been selected for systematic investigations on promising noble-metal films. The sensing mechanism is believed to involve oxygen activation of the metal surface prior to combustion, which provides unique flexibility for developing novel combustible-gas analyzers. Research activities will be focussed primarily on determinations of the sensor sensitivity, selectivity, dynamic range, response time, and optimum operating temperature range. The changes in work function will be detected using an elevated-temperature Kelvin-probe module already under development by the Arizona Instrument Corporation. Success in the proposed research will potentially lead, in Phases II and III, to the commercialization of a new class of compact, versatile combustible gas sensors and/or sensor arrays incorporating a degree of sensitivity, selectivity, speed of response, and stability not previously possible. The worldwide market for combustible gas monitoring and control instrumentation will permit significant market penetration by AZI in a technological area currently dominated by foreign interests.
