摘要 |
<P>PROBLEM TO BE SOLVED: To provide a catalyst for cleaning exhaust gas, which has high performance of removing NOx at low temperature even in either of an oxygen-deficient atmosphere and an oxygen-excess atmosphere. <P>SOLUTION: The catalyst for cleaning exhaust gas, which is arranged in an exhaust passage of an engine, includes: a honeycomb carrier; and catalyst layers 6 formed on the surfaces of cell walls 5 of the honeycomb carrier. The catalyst layer 6 comprises a NOx storage material, a catalytic noble metal and an oxide particle on which the catalytic noble metal is deposited. The oxide particle is a Zr-based compound oxide containing zirconium (Zr) and only at least one metal selected from the group consisting of yttrium (Y), the rare earth metals having the ion radii smaller than that of Y and the alkaline earth metals having the ion radii smaller than that of Y. <P>COPYRIGHT: (C)2010,JPO&INPIT |