US 12,265,054 B2
Sensor element and gas detection method using sensor element
Yusuke Watanabe, Nagoya (JP); and Takayuki Sekiya, Nisshin (JP)
Assigned to NGK INSULATORS, LTD., Nagoya (JP)
Filed by NGK INSULATORS, LTD., Nagoya (JP)
Filed on Mar. 23, 2022, as Appl. No. 17/702,005.
Claims priority of application No. 2021-055733 (JP), filed on Mar. 29, 2021; and application No. 2022-024171 (JP), filed on Feb. 18, 2022.
Prior Publication US 2022/0308010 A1, Sep. 29, 2022
Int. Cl. G01N 27/41 (2006.01); G01N 27/407 (2006.01); G01N 27/409 (2006.01); G01N 33/00 (2006.01)
CPC G01N 27/41 (2013.01) [G01N 27/4071 (2013.01); G01N 27/4075 (2013.01); G01N 27/409 (2013.01); G01N 33/0037 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A sensor element for detecting a target gas to be measured in a measurement-object gas, the sensor element comprising:
a base part in an elongated plate shape, including a plurality of oxygen-ion-conductive solid electrolyte layers stacked;
a measurement-object gas flow part for introduction and flow of the measurement-object gas through one end part in a longitudinal direction of the base part;
a main pump cell including an inner main pump electrode disposed on an inner surface of the measurement-object gas flow part, and an outer pump electrode disposed at a position different from the measurement-object gas flow part on the base part and corresponding to the inner main pump electrode;
a target-gas-decomposing pump cell including a target-gas-decomposing pump electrode disposed at a position farther from the one end part in the longitudinal direction of the base part than the inner main pump electrode on the inner surface of the measurement-object gas flow part, and an outer pump electrode disposed at a position different from the measurement-object gas flow part on the base part and corresponding to the target-gas-decomposing pump electrode;
a residual-oxygen-measuring pump cell including a residual-oxygen-measuring electrode disposed at a position farther from the one end part in the longitudinal direction of the base part than the inner main pump electrode on the inner surface of the measurement-object gas flow part, and an outer pump electrode disposed at a position different from the measurement-object gas flow part on the base part and corresponding to the residual-oxygen-measuring electrode; and
a reference electrode disposed inside the base part to be in contact with a reference gas,
wherein the target-gas-decomposing pump electrode comprises a metal material that has catalytic activity of decomposing the target gas to be measured, and
the residual-oxygen-measuring electrode comprises a metal material that does not have catalytic activity of decomposing the target gas to be measured.