US 12,474,296 B2
Gas sensor
Tatsuya Yoshikawa, Kariya (JP); Yusuke Todo, Kariya (JP); Mitsunobu Nakato, Kariya (JP); Takashi Araki, Kariya (JP); and Yuji Kawasaki, Kariya (JP)
Assigned to DENSO CORPORATION, Kariya (JP)
Filed by DENSO CORPORATION, Kariya (JP)
Filed on May 6, 2021, as Appl. No. 17/313,320.
Application 17/313,320 is a continuation of application No. PCT/JP2019/042850, filed on Oct. 31, 2019.
Claims priority of application No. 2018-211161 (JP), filed on Nov. 9, 2018.
Prior Publication US 2021/0255137 A1, Aug. 19, 2021
Int. Cl. G01N 27/417 (2006.01); G01N 27/406 (2006.01); G01N 27/407 (2006.01); G01N 33/00 (2006.01)
CPC G01N 27/417 (2013.01) [G01N 27/4071 (2013.01); G01N 27/406 (2013.01); G01N 27/4065 (2013.01); G01N 27/4078 (2013.01); G01N 33/0037 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A gas sensor that includes a sensor element,
the sensor element comprising:
a solid electrolyte that has ion conductivity;
a gas chamber that is formed so as to be adjacent to a surface of the solid electrolyte and into which a gas to be detected is introduced;
a pump electrode that is provided on the surface of the solid electrolyte in a state in which the pump electrode is housed inside the gas chamber; and
a sensor electrode that is provided on the surface of the solid electrolyte in a state in which the sensor electrode is housed inside the gas chamber, wherein:
the pump electrode and the sensor electrode contain Au; and
Au content in a surface layer is equal to or greater than 1 mass % and higher than Au content in a reference layer, the surface layer being an area from a surface of the sensor electrode to only a depth of 0.3 nanometers, the reference layer being an area located at only depths ranging from 2 or more to 3 or less nanometers beneath the surface of the sensor electrode.