DEVELOPMENT OF NEW CHEMICAL SENSORS BASED ON LOW-TEMPERATURE PROTON CONDUCTORS

All-solid-state ps sensors operative at room temperature have several advantages over those workable at elevated temperatures. Low-temperature proton conductors such as antimonic acid are demonstrated to be quite promising materials for such sensors. The electrochemical sensors fabricated with these materials allow potentiometric as well as amperometric detection of H-2 in air at room temperature. A newly designed "four-probe type sensor" can generate a signal in proportion to the H-2 concentration without being interfered by humidity. By use of a thick-film fabrication method, the sensor elements can be simplified and/or miniaturized, and as an extension an FET-based micro-H-2 sensor is also available. It is also possible to develop proton conductor sensors to detect other gaseous components such as CO, NH3, O2, and H2O2 as well as bio-related compounds such as glucose.