Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1295813 | Solid State Ionics | 2005 | 6 Pages |
Abstract
Perovskite-type oxide, La0.5Sr0.5CoO3âδ, has large oxygen nonstoichiometry and high electrical conductivity with a large carrier concentration. The oxygen nonstoichiometry, δ, of dense La0.5Sr0.5CoO3âδ was measured in the stream of NOx-O2-N2 system at 873 to 1073 K by means of a thermogravimetric method. Small amounts of NO2 caused large changes in oxygen nonstoichiometry. It seems probable that excessive amounts of oxygen can be incorporated into the bulk due to catalytic decomposition of NO2, and as a result, oxygen potential on the surface of the sample seems to be much higher than that of gaseous phase. EMF measurements for dense La0.6Sr0.4CoO3âδ electrode also revealed that the oxygen potential is affected by NO2. Thus, the gas sensing mechanism of this oxide was found to relate to the change of the bulk property, especially oxygen nonstoichiometry.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Keiji Yashiro, Shigenori Onuma, Maya Sase, Atsushi Kaimai, Takanori Otake, Hiroshige Matsumoto, Tatsuya Kawada, Junichiro Mizusaki,