| 摘要 |
PURPOSE:To obviate receiving of the influence of combustible gases and nitrogen oxide by providing a catalyst layer on the surface of a threshold electric current type oxygen sensor element thereby permitting arrival of equilibrium gases at electrodes. CONSTITUTION:A solid electrolyte body 1 of a sensor element I is a sintered body made by preparing zirconium oxide powder and yttrium oxide powder at 9:1 molar ratio and pressure molding these. platinum electrodes 4a, 4b of 1mu thickness are formed by a sputtering method on both surfaces of such body 1. Lead wires 2, 2 are stuck by pressure to these. A porous coating layer 5 is formed by melt spraying Mgo.Al2O3 to prescribed thickness by a plasma melt spraying method. This sintered body is dipped in a slurry consisting of particles of gamma-Al2O3, cheoroplatinic acid and rhodium chloride to stick the slurry on the surface of the sintered body, after which it is subjected to thermal decomposition treatment, whereby the oxygen sensor is obtained. |
