Abstract: An object of the present invention is to provide an exhaust gas purifying catalyst composition and an exhaust gas purifying catalyst, each of which has improved exhaust gas purification performance, and the present invention provides an exhaust gas purifying catalyst composition containing a Ce-based oxide particle, a Ce—Zr-based composite oxide particle, and a noble metal element, wherein an amount of Ce in terms of CeO2 in the Ce-based oxide particle is 80% by mass or more based on the mass of the Ce-based oxide particle, wherein an amount of Ce in terms of CeO2 in the Ce—Zr-based composite oxide particle is 5% by mass or more and 90% by mass or less based on the mass of the Ce—Zr-based composite oxide particle, and wherein a crystallite size of CeO2 in the Ce-based oxide particle is 10 nm or more.

Abstract: An object of the present invention is to provide an exhaust gas purification catalyst with improved exhaust gas purification performance, and in order to achieve such an object, the present invention provides an exhaust gas purification catalyst (1A) including a substrate (10) and a catalyst layer (20) provided on the substrate (10), wherein the catalyst layer (20) includes a first layer (21) containing Rh, and Pd and/or Pt, and a second layer (22) containing Rh, and Pd and/or Pt, wherein a total content of Zr and Ce in terms of oxide and a content of aluminum element in terms of oxide in the first layer (21) are 70% by mass or more and 15% by mass or less, respectively, based on a mass of the first layer (21), and wherein a content of aluminum element in terms of oxide and a total content of Zr and Ce in terms of oxide in the second layer (22) are 75% by mass or more and 15% by mass or less, respectively, based on a mass of the second layer (22).

Abstract: An object of the present invention is to provide an exhaust gas purifying catalyst composition and an exhaust gas purifying catalyst, each of which has improved exhaust gas purification performance, and the present invention provides an exhaust gas purifying catalyst composition containing a Ce-based oxide particle, a Ce—Zr-based composite oxide particle, an Al-based oxide particle, and a noble metal element, wherein an amount of Ce in terms of CeO2 in the Ce-based oxide particle is 90% by mass or more based on a mass of the Ce-based oxide particle, wherein an amount of Ce in terms of CeO2 in the Ce—Zr-based composite oxide particle is 5% by mass or more and 90% by mass or less based on a mass of the Ce—Zr-based composite oxide particle, wherein the Ce-based oxide particle has an average particle size of 0.10 ?m or more and 15 ?m or less, and wherein an amount of the Ce-based oxide particle in the exhaust gas purifying catalyst composition is 2.

Abstract: An object of the present invention is to provide an exhaust gas purification catalyst with improved exhaust gas purification performance, and in order to achieve such an object, the present invention provides an exhaust gas purification catalyst (1A) including a substrate (10) and a catalyst layer (20A) provided on the substrate (10), wherein a content of aluminum element in terms of oxide and a content of barium element in a first layer (21) of the catalyst layer (20A) are 15% by mass or more and 3% by mass or more, respectively, based on a mass of the first layer (21), and wherein a total of a content of zirconium element in terms of oxide and a content of a rare earth element in terms of oxide, a content of aluminum element in terms of oxide, and a content of barium element in a second layer (22) of the catalyst layer (20A) are 80% by mass or more, less than 15% by mass, and less than 3% by mass, respectively, based on a mass of the second layer (22).

Abstract: An object of the present invention is to provide an exhaust gas purifying catalyst composition and an exhaust gas purifying catalyst, each of which has improved exhaust gas purification performance, and the present invention provides an exhaust gas purifying catalyst composition containing a Ce-based oxide particle, a Ce—Zr-based composite oxide particle, and a noble metal element, wherein the Ce-based oxide particle contains at least one type of additional element selected from Al, Mg, La, Pr, Y, and Nd, and wherein an amount of the at least one type of additional element in terms of oxide in the Ce-based oxide particle is 0.1% by mass or more and 20% by mass or less based on a mass of the Ce-based oxide particle.

Abstract: An exhaust gas purification catalyst is provided which can be more enhanced in NOx purification performance.