A catalyst for purifying exhaust gas

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PROBLEM TO BE SOLVED : To improve heat resistance by controlling the growth of noble metal particles in a catalyst for purifying exhaust gas in which the noble metal is supported on a carrier containing zirconia by providing the carrier containing at least one kind of oxide of a rare earth element excluding cerium and zirconia and the noble metal supported on the carrier. SOLUTION : A carrier of a catalyst for purifying exhaust gas is formed from at least one kind of oxide of a rare earth element excluding cerium and zirconia. By mixing the oxide with zirconia, the growth of noble metal particles can be controlled to improve heat resistance even when used at a high temperature. As the rare earth element excluding cerium, yttrium (Y) indicates particularly excellent effects. The atomic ratio of the rare earth element to zirconium in the carrier is preferably 0.1/0.9-0.9/0.1. As the noble metal supported on the carrier is preferably Pt high in activity.