| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method and device for easily and accurately determining whether a noble metal catalyst has been deteriorated or not, by using stagnation time in which an output of a gas sensor element stagnates. <P>SOLUTION: A gas sensor element 100 includes: a detecting part 10 including at least a solid electrolyte layer 3 provided on both sides, with a pair of electrodes 4 including a measured gas side electrode 41 and a reference gas side electrode 42; a catalyst layer 20 carrying a noble metal catalyst 22 surrounding a part of or the entire detecting part 10; and a protecting layer 30 surrounding the catalyst layer 20. A method for determining whether the noble metal catalyst 22 in the gas sensor includes: a step of measuring a stoichiometric stagnation time of the gas sensor element 100 around stoichiometric; and a step of comparing the stoichiometric stagnation time with a time period which is a threshold for determining the deterioration of the noble metal catalyst, and determining that the noble metal catalyst is deteriorated when the stoichiometric stagnation time is below the threshold. <P>COPYRIGHT: (C)2013,JPO&INPIT |
