Exhaust gas purification catalyst

Abstract

An object of the present invention is to provide an exhaust gas purification catalyst including a substrate, a first catalyst layer provided on the substrate, and a second catalyst layer provided on an upside of the first catalyst layer, wherein the first catalyst layer contains Pd, wherein the second catalyst layer contains Rh, and wherein the exhaust gas purification catalyst can suppress a decrease in exhaust gas purification performance after exposure to a high temperature environment and a decrease in exhaust gas purification performance after exposure to phosphorus, and the present invention provides an exhaust gas purification catalyst (1) including a substrate (10), a first catalyst layer (20) provided on the substrate (10), and a second catalyst layer (30) provided on an upside of the first catalyst layer (20), wherein the first catalyst layer (20) contains Pd, and wherein the second catalyst layer contains Rh and a complex oxide containing Ce, Zr, and Al, wherein the exhaust gas purification catalyst (1) satisfies at least one of the following conditions A and B: (A) the first catalyst layer (20) contains Sr, and a content of Sr in terms of metal in the first catalyst layer (20) is 0.1% by mass or more, based on a mass of the first catalyst layer (20); and (B) the second catalyst layer (30) contains Sr, and a content of Sr in terms of metal in the second catalyst layer (30) is 0.1% by mass or more, based on a mass of the second catalyst layer (30).

Dependencies are inferred from the claim text.