| 摘要 |
PROBLEM TO BE SOLVED: To obtain an exhaust gas cleaning apparatus using brownmillerite type composite oxide particles and fine noble metal particles high in catalytic activity, having a stable structure and excellent in durability. SOLUTION: An exhaust gas cleaning catalyst 3 is constituted of catalyst particles 3 comprising a brownmillerite type composite oxide represented by the formula: A2 B2 O5 wherein at least two elements selected from Ba, Y, Sr, Ca, Ti, Ce, Zr and Ge are set to constitutional elements A, B and fine reducing catalyst particles 4 comprising at least one noble metal selected from Rh, Ru, Pd, Ir, Pt and Au to be arranged to the same layer on the surface of a heat- resistant honeycomb carrier 5. |
