| abstract |
A catalyst for clarifying an exhaust gas containing a carrier and, carried thereon, an active component comprising a noble metal, wherein the carrier comprises a core portion comprising a cubic or tetragonal system stabilized zirconia based composite oxide containing at least one stabilizing element and, formed on the surface of the core portion, a surface layer portion comprising a heat-resistant zirconia based composite oxide, wherein the surface layer portion has a specific surface area greater than that of the core portion, and wherein a part of the noble metal forms a solid solution with the zirconia based composite oxide in the surface layer portion and the remainder of the noble metal is carried on the surface of the surface layer portion. |