| 摘要 |
PURPOSE:To make it possible to measure O2 partial pressure with high percision even at comparatively lower temperature, make reproducibility satisfactory and improve durability by immersing porous insulated ceramic substrate into aqueous sensitizer solution of Co salt base and letting the sensitizer adhere to said substrate by repeating drying and baking operations. CONSTITUTION:First the process of immersing porous alumina plate in aqueous solution of nickel nitrate, etc., drying and baking a few times. Then platinum lead wire 3 is placed on said substrate, and platinum paste is printed, baked so that an electrode 2 is formed. Following this procedure, the substrate is soaked in a blended solution of 0.7mol/liter of cobalt nitrate and 0.3mol/liter of magnesium nitrate for 5 seconds, dried and baked at 600 deg.-700 deg.C. These ooerations are repeated approximately 10 times. After that, final baking is carried out at 1,000 deg.C to form an oxygen sensor supporting compound oxides of cobalt and magnesium. Thus it is possible to measure with precision even at comparatively low temperatures (650 deg.- 700 deg.C) and provide improved reproducibility. |
