| 摘要 |
PROBLEM TO BE SOLVED: To provide a device for detecting failure of an NHsensor in which an NHdetection electrode is constituted of a photocatalyst material.SOLUTION: An NHsensor comprises: an NHdetection electrode which includes a photocatalyst material, and is exposed in an exhaust pipe; a reference electrode which is constituted of a material different from a material constituting the NHdetection electrode, and exposed in the exhaust pipe; and an oxygen ion conductive solid electrolyte body to which the reference electrode and the NHdetection electrode are joined. The sensor generates an electromotive force MAIN-EMF corresponding to NHand HO between the NHdetection electrode and the reference electrode. A method for detecting failure of the NHsensor comprises an HO amount change step (S3) of changing an amount of the HO in the exhaust pipe, and failure detection steps (S4 to S9) of acquiring a change of the electromotive force MAIN-EMF occurring when the HO is changed, and detecting a failure of the NHsensor on the basis of the change of the electromotive force MAIN-EMF.SELECTED DRAWING: Figure 8 |
