公开(公告)号：US20180017520A1

公开(公告)日：2018-01-18

申请号：US15650017

申请日：2017-07-14

Applicant: DENSO CORPORATION

Inventor： Yusuke TODO ,  Mitsunobu NAKATO ,  Hiroaki YOTO ,  Hiroki ICHIKAWA

IPC: G01N27/417 ,  C22C5/04 ,  G01N27/419 ,  G01N27/30

CPC classification number: G01N27/417 ,  C22C5/04 ,  G01N27/304 ,  G01N27/4073 ,  G01N27/419

Abstract: A gas sensor includes a sensor element. The sensor element includes; a solid electrolyte body that has oxygen ion conductivity and includes a first main surface exposed to a gas to be measured and a second main surface exposed to a reference gas; a sensor electrode that is provided on the first main surface and detects a specific gas component in the gas to be measured; and a reference electrode that is provided on the second main surface. The sensor electrode is made of a Pt—Rh alloy that contains 30 mass % to 70 mass % Pt and 70 mass % to 30 mass % Rh, when an overall noble metal component is 100 mass %. A variation amount of the Rh content of the Pt—Rh alloy from an outermost surface to a depth of 350 nm in a thickness direction of the sensor electrode is within a range of up to 10 mass %.