| 摘要 |
An electrode formed on an oxygen-ion conductive solid electrolyte body of an oxygen sensing element such that the electrode is exposed to a measurement fluid to be measured, for detecting a concentration of oxygen in the fluid. The electrode is formed of a porous cermet layer which has a thickness of at least 3 microns. The porous cermet layer includes as major components thereof an oxygen-ion conductive solid electrolyte, and at least two platinum-group metals which are selected from the platinum group and which includes platinum and rhodium. A content of said rhodium and a total content of the above at least two platinum-group metals are determined so as to satisfy the following formulas: R/M=0.2 to 0.8, and M/(SE+M)=0.3 to 0.8, where, R=volume % of rhodium included in the cermet layer, M=total volume % of the at least two platinum-group metals, and SE=volume % of the oxygen-ion conductive solid electrolyte included in the cermet layer.
|
