Abstract
A systematic investigation has been carried out on the time dependence of the response to NO and CO of a gas sensor with a thick porous film of Bi 2Sr 2CaCu 2O 8+ x (BSCCO). The oxidation of reducing gases such as NO and CO by lattice oxygen occurs in parallel with desorption of NO 2 and CO 2, respectively, in the whole range of temperatures investigated. An extension of a reported model has been proposed in order to describe the response of the sensor. The time dependence of the electrical resistivity can be interpreted by assuming a conductivity dominated by Schottky barriers at grain boundaries. A kinetic model underlying the temperature dependence of the sensitivity to NO and the selectivity against CO is discussed. The high sensitivity to NO as compared to that to CO is attributed to the high adsorption rate of NO at low temperatures. The good selectivity at high temperatures is attributed to the rapid increase of the desorption rate of CO and/or CO 2 with increasing temperature. The response time increases with increasing equilibrium sensitivity S 0. The recovery time decreases with increasing S 0. They both decrease with increase of the desorption rate of CO(NO) and CO 2(NO 2).
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
