CATALYST FOR CLEANING EXHAUST GAS

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PROBLEM TO BE SOLVED : To provide a catalyst for cleaning exhaust gas capable of suppressing the transfer of Rh and having an excellent NOx cleaning performance. SOLUTION : The catalyst for cleaning exhaust gas includes : a base material 1 forming a gas passage where exhaust gas flows; a lower catalytic layer 2 formed on the surface of the base material 1; and an upper catalytic layer 3 formed on the surface of the lower catalytic layer 2. The lower catalytic layer 2 has a lower catalytic precious metal including at least one kind of Pt and Pd, and a lower carrier carrying the lower catalytic precious metal. An upper catalytic layer 3 has an upper catalytic precious metal including Rh, and an upper carrier carrying the upper catalytic precious metal. The upper carrier comprises at least one kind or more selected from the group consists of Ce, Zr, Al and a rare earth element other than Ce and an alkaline earth element; and an inorganic mixed oxide including Nd. The inorganic mixed oxide comprises an inner part and a coating layer coating the surface of the inner part, and Nd is ubiquitous in the coating layer. COPYRIGHT : (C)2011, JPO&INPIT