| 摘要 |
PROBLEM TO BE SOLVED: To provide an NOx gas sensor for which the light-off time after can be set start short, and which can prevent degradation in the S/N of the sensor output. SOLUTION: The NOx gas sensor 1 has a structure in which a first pump cell 11, an oxygen concentration detection cell 12 and a second pump cell 13 are laminated via insulating layers 14 and 15 mainly consisting of alumina. A second diffusion resistor 17 formed of a porous material is formed around a second outer electrode 25b provided on the second pump cell 13, and a second chamber S2 is formed between a second inner electrode 25a and a second diffusion resistor 17. The NOx gas sensor in which the variable V/A, comprising the capacity V of the second chamber S2 and the electrode area A of the second inner electrode 25a, is set to be between 0.01 [mm] and 0.1 [mm] can shorten the light-off time, and prevent any degradation of the S/N ratio. |
