Catalyst for purifying an exhaust gas

摘要

A catalyst for purifying an exhaust gas includes a composite oxide support and a platinum structural layer. The composite oxide support has a spinel structure expressed by M . Al2O4 in which M is an alkaline-earth metal. The platinum structural layer is formed on a surface of the composite oxide support and includes a matrix composed mainly of an alkaline-earth metal oxide in which platinum clusters are dispersed uniformly. A composite oxide layer can be interposed between the composite oxide support and the platinum structural layer. Also disclosed is an optimum process for producing the catalyst. <IMAGE>