Resistive oxygen sensor using ceria-zirconia sensor material and ceria-yttria temperature compensating material for lean-burn engine

Abstract

Temperature compensating materials were investigated for a resistive oxygen sensor using Ce0.9Zr0.1O2 as a sensor material for lean-burn engines. The temperature dependence of a temperature compensating material should be the same as the sensor material; therefore, the Y concentration in CeO2-Y2O3 was optimized. The resistance of Ce0.5Y0.5O2-δ was independent of the air-to-fuel ratio (oxygen partial pressure), so that it was confirmed to function as a temperature compensating material. Sensor elements comprised of Ce0.9Zr0.1O2 and Ce0.5Y0.5O2-δ were fabricated and the output was determined to be approximately independent of the temperature in the wide range from 773 to 1,073 K. © 2009 by the authors.