| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that when a bivalent or a trivalent cathion solid solution volume is to be increased to increase an oxygen failure volume in a ceria system solid electrolyte, a conductivity decreases and an improvement in an oxide ion conductivity is made hard to attain. <P>SOLUTION: The ceria system solid electrolyte is structured with a complex oxide sintered body expressed in a composition formula: (M<SP>3+</SP><SB>x</SB>N<SP>2+</SP><SB>1-x</SB>)<SB>y</SB>Ce<SB>1-y</SB>O<SB>2-d</SB>. A crystal phase constituting the sintered body is mainly of a single fluoric type structure by identification of the crystal phase by an X-ray diffraction test with a particle size of the sintered body crystal of 50 nm or more and 150 nm or less based on a starting grain size, or 5 μ or more and 20 μ or less, with a particle diameter inside the sintered body made dense to not less than 95% of theoretical density in a relative density, with fluctuation of each particle within ±50% from an average particle size and having a micro domain inside the sintered body particles with average size of 1 nm or more and 10 nm or less, and with an interface of a fluoric crystal as a parent phase and the micro domain perfectly matched. <P>COPYRIGHT: (C)2004,JPO |
