Novel composite oxide and oxygen storage material containing the same

Abstract

Provided is an inexpensive oxygen storage material having an excellent oxygen release performance at low temperature. One aspect of the present disclosure relates to a composite oxide having a composition represented by a general formula Ce2-w-x′AwA′x′B1-y′-zB′y′B″zO6-w/2-x′-y′/2-z. In the formula, A is one or more elements selected from rare-earth metal elements excluding Ce, A′ is one or more elements selected from alkaline earth metal elements, B is one or more elements selected from the group consisting of Ti and Group 14 elements, B′ is one or more elements selected from the group consisting of Group 13 elements, B″ is one or more elements selected from the group consisting of Group 12 elements, 2−w−x′, w, x′, 1−y′−z, y′, z, and 6−w/2−x′−y′/2−z are mole ratios of Ce, A, A′, B, B′, B″, and O, respectively when B+B′+B″ is assumed to be 1, w, x′, y′, and z satisfy 0≤w<2, 0≤x′<0.5, 0≤y′≤1, 0≤z≤0.5, respectively, and w+x′ satisfies 0≤w+x′<2, and y′+z satisfies 0≤y′+z≤1.

Dependencies are inferred from the claim text.