NSF Award
9561471
This SBIR Phase I project will develop new sensor materials for chemical characterization of mutlicomponent gas streams. There is a growing need for chemical sensors for the continuous, on line monitoring of gaseous process and emission streams. Micron sized devices that are sensitive, operate under the adverse conditions frequently required for many energy related applications, and can discriminate species in multicomponent mixtures are currently unavailable. The objective of the proposed work is to develop robust chemical sensing devices which will quantify the gas composition based on changes in the electrical conductivity of the transducer produced by adsorption of the target gas(es) and identify the species based on the temperature at which they desorb from the transducer surface as the transducer is heated linearly. This firm has identified conductive ceramics which hold great promise for use as sensor materials because they are refractory, possess high electrical conductivities, reversibly adsorb/desorb a number of gases of interest and can be produced in the form of high surface area films. This firm will show that sensor transducers based on these materials will be amenable to miniaturization, highly selective, operable at extreme temperatures and inexpensive. The Phase I research will demonstrate the feasibility of these materials by fabricating high surface area transducer films and evaluating their ability to detect and discriminate H2 and NO, common process gases. Changes in the electrical conductivity on adsorption of H2 and NO will be evaluated using the four point probe method and the ability to discriminate these gases will be determined using temperature programmed desorption techniques. The thermal and chemical stabilities will be evaluated in H2 and NO at temperatures up to 1000 ÝC. This project will lead to a new class of materials for on line sensing of gaseous streams. These sensors will be based on materials which are ideal for operation in high temperature and corrosive environments. Process control and continuous emissions monitoring represent two broad areas of potential commercial application. Combustion based processes would benefit in both respects. For example, emissions feedback to engine control computers can both improve energy efficiency and reduce emissions.
