| 摘要 |
PURPOSE:To provide a compact gas leak detecting element which has a high performance, by a method wherein an electrode surface, where a gas-sensitive substrate, consisting of an oxygen ion conductive solid electrolyte, makes contact with gas to be detected, is covered with a catalyst layer. CONSTITUTION:ZrO2 containing 5-8mol% Y2O3 is used as a tubular oxygen ion conductive solid electrolyte 1, pasty platinum is sintered to electrodes 2 and 3, and a molybdenum catalyst layer (a ratio of Al2O3 is 10wt%, a molar ratio of V/Mo is 0.1) is further formed on the surface of the inner electrode 3. If the element so constituted is heated to about 450 deg.C to measure a detecting limit against CCl2F2, CHCl2F2, CCl2F2 is 6X10<-6>cc/sec, and CHCl2F2 is 8X10<-6>cc/ sec. Resulting from the use of said catalyst, a polarity of an electromotive force, generated when the catalyst contacts organic gas such as Co, C2H5OH, differs from that which is produced in the case of halogenated carbon hydride gas, and thereby a sharply improved selectivity can be obtained. |
