Synthesis of Mesoporous Tin Oxide for Chemical Gas Sensors

50532-98-I Synthesis of Mesoporous Tin Oxide for Chemical Gas Sensors--CeraMem Corporation, 12 Clematis Avenue, Waltham, MA 02154-7011; (781) 899-4495 Dr. Bruce A. Bishop, Principal Investigator Dr. Robert Goldsmith, Business Official DOE Grant No. DE-FG02-98ER82549 Amount: $75,000 Chemical gas sensors based on metal oxide semiconductors are used in a wide variety of applications. Devices fabricated by thin film deposition techniques have been replacing those made by more traditional thick film processes due to better sensor reproducibility and long term stability. However, thin film sensors have low surface area and are susceptible to surface poisoning. In order to expand the usefulness of chemical gas sensors, novel film formation processes leading to improved film microstructures need to be developed. This project will fabricate a mesoporous metal oxide semiconductor as a possible alternative to traditional thick and thin film sensor layers. Tin oxide will be used as a model material. If successfully fabricated, the mesoporous structure¿s high surface area will mitigate the effects of poisoning, and it¿s very good structural stability will improve reproducibility and long term stability of sensor response. Phase I will first develop the process to make mesoporous powders of tin oxide. Using this procedure, thin films of mesoporous tin oxide will be fabricated on substrates suitable for use in sensor devices. Such devices will be fabricated and tested at typical use conditions for sensor response and stability. Commercial Applications and Other Benefits as described by the awardee: Applications of these new sensor devices include relative humidity sensing for industrial and consumer driers and ovens, natural gas sensors for explosion-limit detectors and alarms, poison gas sensors for carbon monoxide and hydrogen sulfide, nitrogen oxide sensor for air pollution control processes, and ethanol sensors for fermentation control and breathalyzer test equipment._