| 摘要 |
PURPOSE:To improve the precision in detection of the concentration of a nitrogen oxide by an exhaust gas sensor and thus to enable improvement of the reliability. CONSTITUTION:An oxygen pump part 1 is constructed by forming electrodes 3 and 4 on an oxygen ion conductor 2 and a porous oxide semiconductor 5 being a P-type semiconductor is provided in lamination in this oxygen pump part 1. The electrodes 3 and 4 are connected to a variable power source 18, while electrodes 4 and 6 are connected to a power source 24. A nitrogen oxide from a gas diffusion chamber 14 is decomposed on the surface of the oxide semiconductor 5 by a catalytic decomposition reaction and the concentration of the nitrogen oxide is detected on the basis of a resistance value of the oxide semiconductor 5. |
