| 摘要 |
<P>PROBLEM TO BE SOLVED: To enhance the capacity or durability of an exhaust gas purifying catalyst. <P>SOLUTION: Rh doped CeZr type composite oxide powder, wherein CeZr composite oxide particles containing Pr, La, Y or Nd or compounded with Al<SB>2</SB>O<SB>3</SB>are doped with Rh in a solid solution state, and noble metal supported heat-resistant powder, wherein a noble metal (Pt or Pd) is supported on heat-resistant particles comprising La-containing Al<SB>2</SB>O<SB>3</SB>particles, BaSO<SB>4</SB>particles or composite particles of a CeZr type composite oxide and Al<SB>2</SB>O<SB>3</SB>, are contained in the catalyst layer 2 of a honeycomb carrier 1. The noble metal supported heat-resistant power is contained in the upstream side range of the exhaust gas stream of the catalyst layer 2 and the support amount of the noble metal per the unit volume of the honeycomb carrier is smaller than that of the upstream side range or zero within the downstream side range succeeding to the upstream side range. <P>COPYRIGHT: (C)2011,JPO&INPIT |
