| 摘要 |
PROBLEM TO BE SOLVED: To provide a high sensitivity, high response sensor which is hydrogen selective under high temperature by arranging a detection electrode of a metal oxide semiconductor selected from a group of ZnO, SnO2 and In2 O3 , and a reference electrode containing no metal oxide semiconductor on the surface of an oxygen ion conductive solid electrolyte. SOLUTION: The solid electrolyte hydrogen sensor 2 is provided with a detection electrode 10 by forming a ZnO layer 6 at the forward end of a YSZ (yttrium stabilized zirconia) tube 4 and stretching a Pt metal mesh 8 thereon for the purpose of electrical contact. A Pt layer 12 is then formed at the forward end on the inner surface of the YSZ tube 4 and a Pt metal mesh 14 is stretched thereon to provide a reference electrode 16. A heater 20 is contained in the YSZ tube 4 and heated up to a working temperature of 450-600 deg.C. High sensitivity to hydrogen is achieved for ZnO, SnO2 and In2 O3 but variation in the electromotive force of hydrogen is low for other metal oxides. Furthermore, ZnO, SnO2 and In2 O3 have high hydrogen sensitivity and low CO sensitivity and the sensor exhibits hydrogen selectivity. |
