Potentiometric hydrocarbon sensor for detecting gaseous hydrocarbons in a combustion exhaust gas com

Potentiometric hydrocarbon sensor comprises an electrode structure consisting of a reference electrode (3) and a working electrode (4) in contact with a solid body electrolyte (2). The working electrode is made from a perovskite mixed oxide of the formula : A1-yB11-x-zB2zCuxOn (where A = rare earth; B1 and B2 = Fe, Al, Sc, Bi, Cr, Mn, Co or Ga; x = 0.05-0.4; y = 0-0.3; z = 0-0.1; and n = 2.5-3.0).