EXHAUST GAS PURIFICATION CATALYST

摘要

An exhaust gas purifying catalyst is provided which exhibits high catalytic performance and brings about decrease in the amount of noble metals used. The exhaust gas purifying catalyst (1) includes a catalyst substrate (3), and a catalyst coating layer (5, 7) which is formed on the catalyst substrate (3) and contains a noble metal and a refractory inorganic oxide. The exhaust gas purifying catalyst is characterized in that the catalytic coating layer (5, 7) has a layered structure including an inside layer (5) and an outside layer (7). The inside layer (5) contains Pd and Pt as the noble metal in a weight ratio of 3:1 to 20:1, while the outside layer (7) contains Rh as the noble metal.