CATALYST FOR EXHAUST GAS PURIFICATION

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Disclosed is a catalyst for exhaust gas purification, which exhibits high NOx purification performance under high temperature conditions with use of a small amount of a noble metal. Specifically disclosed is a catalyst (1) for exhaust gas purification, which comprises a base (2), a lower layer (3) formed on the base (2) and containing a first complex oxide and palladium, and an upper layer (4) formed on the lower layer (3) and containing a second complex oxide and rhodium. The first complex oxide contains cerium, zirconium and an element selected from the group consisting of rare earth elements other than cerium and alkaline earth elements. In the first complex oxide, the mass ratio of platinum to palladium is within the range from 1/50 to 1/20. The second complex oxide contains zirconium and an element selected from the group consisting of rare earth elements other than cerium and alkaline earth elements. In the second complex oxide, the atomic ratio of cerium to zirconium is smaller than that in the first complex oxide.