| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a catalyst for purification of exhaust gas having excellent durability by suppressing growth of grains of a catalyst noble metal further. <P>SOLUTION: The catalyst comprises a highly heat-resistant oxide 1 having a multi-layer structure containing a clearance 10 between layers, a solid solution precipitated layer 2 which comprises a compound formed in the interlaminar clearance 10, solid-dissolving a noble metal in an oxidative atmosphere and allowing the solid-dissolving noble metal to precipitate in a reducing atmosphere, and a catalyst noble metal 3 contained in the solid solution precipitated layer 2. Since the layer 2 formed in the interlaminar clearance 10 is thin, the response between solid dissolving of the catalyst noble metal in an oxidative atmosphere and precipitation of the catalyst noble metal in a reductive atmosphere becomes sharp. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
