Patent ID: 7943024
Filing Date: 2011-05-17
Classification: G01N

Abstract:
1. An NOx sensor element including an electrochemical cell, wherein a measuring electrode formed of a cermet of an electrode metal material capable of reducing or decomposing an NOx component of a measurement gas and a ceramic material is formed on a solid electrolyte body, said NOx sensor element being arranged to obtain a concentration of said NOx component of said measurement gas by measuring an amount of oxygen produced by reduction or decomposition of the NOx component by said measuring electrode, wherein an improvement comprises: said measuring electrode being constituted by a porous electrode comprising a sintered body in the form of a thin film comprising an electrode metal material and a ceramic material and which has a multiplicity of pores formed therein, wherein an entirety of said porous electrode is porous, and wherein said sintered body has a total pore volume in a range of at least 0.017 ml/g to not more than 0.053 ml/g and a peak pore diameter in a range of at least 0.43 μm to not more than 1.1 μm, as measured by a mercury penetration method.