| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a catalyst for exhaust gas purification containing an occlusion material in which a catalyst noble metal can exert a catalytic function sufficiently even in a mass ratio range of ZrO<SB>2</SB>except the range of 20-30 mass% or 65-90 mass%, as an oxygen storage material arranged between crystal lattices or lattice points of a double oxide containing Ce and Zr. <P>SOLUTION: In the catalyst for exhaust gas purification which has a catalyst layer containing a cerium-zirconium (CeZr) double oxide, the double oxide contains ceria (CeO<SB>2</SB>) and zirconia (ZrO<SB>2</SB>) in the range that a mass ratio of ceria to a total mass of ceria and zirconia becomes to be ≥36 mass% and ≤64 mass%, and at the same time, contains a rare-earth metal except cerium (Ce) as an oxide to a total mass of the double oxide in the range of ≥3 mass% and ≤20 mass%. <P>COPYRIGHT: (C)2007,JPO&INPIT |
