STACKED MIXED LAYER IRREGULAR CRYSTAL STRUCTURE DELAFOSSITE-TYPE OXIDE AND METHOD FOR PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a stacked mixed layer irregular crystal structure delafossite-type oxide having a new crystal structure and a peculiar oxygen absorbing/releasing characteristic, and to provide a method for producing the same. SOLUTION: The stacked mixed layer irregular crystal structure delafossite-type oxide expressed by the formula ABO2 (A is Cu, Ag, Pt, Pd or Au; B is a trivalent metal comprising Sc, Al, Ga, In, Tl, Y, Ln, Cr, Fe, Co, Ni or Ti; and O is oxygen), wherein a mixture layer of a 2H-polymorphic structure layer and a 3R-polymorphic structural layer forms a stacked irregular crystal structure, is characterized by having oxygen absorbing/releasing characteristic depending on the heating temperature without change of atomic configuration of the basic skeleton. This oxide is user for oxygen absorbing/releasing materials, an NOx decomposition catalyst. The delafossite-type oxide in which a mixture layer of 2H-polymorphic structural layer and a 3R- polymorphic structural layer forms a stacked irregular crystal structure is obtained by mixing powder raw materials of stoichiometric composition, pressure forming, firing in the air and quenching.