| 摘要 |
PROBLEM TO BE SOLVED: To provide a catalyst for clarification of exhaust gas which has high NOx absorbing action even when oxygen becomes excess. SOLUTION: At least one element (a) selected from among platinum, palladium and rhodium, a composite (b) (composite I) wherein (La1-x Ax )1-α BO1-δ , 0<x<1, 0<α<0.2, 0<=δ<=1, and A is at least one element selected from Ba and K and B is at least one element selected from among iron, cobalt, nickel and manganese and a composite (c) (composite-II) expressed by Cey Zr1-y O2 wherein 0<y<1 are incorporated and 20-80% of the precious metal are a catalyst carried on composite II, which clarifies nitrogen oxide under oxygen excess atmosphere. |
