摘要 |
<p>Disclosed is a gas sensor (10A) for measuring a NOx concentration comprising a main pumping cell (44) and a detecting electrode (60), the main pumping cell (44) including an electrode (an inner pumping electrode (40) and an outer pumping electrode (42)) having no decomposing/reducing ability for NOx or a low decomposing/reducing ability for NOx, to be used so that an oxygen concentration in a first chamber (18) is controlled to have a predetermined value at which NO is not substantially decomposable, and the detecting electrode (60) having a certain decomposing/reducing ability for NOx or a high decomposing/reducing ability for NOx, to be used so that NOx is decomposed to measure the NOx concentration by measuring an amount of oxygen produced during this process, wherein a buffering space (22) is provided between a gas-introducing port (24) and the first chamber (18). Accordingly, it is possible to avoid any influence of exhaust gas pressure pulsation generated in a measurement gas and improve the measurement accuracy on the detecting electrode. <IMAGE></p> |