SOLID ELECTROLYTE FOR OXYGEN SENSOR, AND OXYGEN SENSOR

摘要

PROBLEM TO BE SOLVED: To provide a solid electrolyte for oxygen sensors, having excellent characteristics of ion conductivity.;SOLUTION: A solid electrolyte for oxygen sensors consists of a BaZrO₃-based perovskite type oxide in which at least one kind of rare earth element MA selected from Dy, Nd, Pr and Tb is doped, and a part of Zr is replaced by the rare earth element MA. Especially, it is preferable that the solid electrolyte has a composition represented by composition formula of BaZr_1-xMA_xO_3-δ, where 0.05≤x≤0.2 and 0≤δ≤x/2. The solid electrolyte for oxygen sensors exhibits characteristics that ionic conductivity is significantly varied corresponding to an oxygen concentration since at least one kind of rare earth element MA selected from Dy, Nd, Pr and Tb is doped, and a part of Zr in BaZrO₃ is replaced by the rare earth element MA. This is caused by the fact that a valence of the element MA in BaZrO₃ is varied from trivalent exhibiting ionic conduction to tetravalent not exhibiting ionic conduction by oxygen concentration.;COPYRIGHT: (C)2014,JPO&INPIT