Abstract: An exhaust gas-purifying catalyst includes first particles of oxygen storage material, second particles of one or more acidic oxides interposed between the first particles, and third particles of one or more precious metal elements interposed between the first particles, wherein a spectrum of a characteristic X-ray intensity for one of constituent elements of the acidic oxide(s) other than oxygen and a spectrum of a characteristic X-ray intensity for one of the precious metal element(s) that are obtained by performing a line analysis using energy-dispersive X-ray spectrometry along a length of 500 nm have a correlation coefficient of 0.70 or more.

Abstract: An exhaust gas-purifying catalyst includes first particles of oxygen storage material, second particles of one or more rare-earth elements other than cerium and/or compounds thereof interposed between the first particles, and third particles of one or more precious metal elements interposed between the first particles, wherein a spectrum of a characteristic X-ray intensity for one of the rare-earth element(s) and a spectrum of a characteristic X-ray intensity for one of the precious metal element(s) that are obtained by performing a line analysis using energy-dispersive X-ray spectrometry along a length of 500 nm have a correlation coefficient of 0.68 or more.

Abstract: The present invention relates to a catalyst for purifying exhaust gases emitted from the internal combustion engines. The exhaust-gas-purifying catalyst in this invention, comprising: a catalyst support substrate and a plurality of catalyst layers formed on a surface of the catalyst support substrate and having an exterior-surface layer for forming a surface of the plural catalyst layers, and the exterior-surface layer including a loading layer formed by fireproof inorganic oxide; at least one catalytic metal selected from the group consisting of platinum, palladium and rhodium, and supported on the loading layer; stabilized zirconia loaded on the loading layer; and cerium-zirconium composite oxide loaded on the loading layer, and the stabilized zirconia including zirconia and oxide formed by at least one additive member selected from the group consisting of yttrium, neodymium, praseodymium and lanthanum.

Abstract: A high NOx-purifying performance at high temperature conditions is achieved with a small amount of precious metal used. An exhaust gas-purifying catalyst includes a substrate, a lower layer formed on the substrate and including a first composite oxide, palladium and platinum, and an upper layer formed on the lower layer and including a second composite oxide and rhodium. The first composite oxide includes cerium, zirconium, and an element selected from the group consisting of rare-earth elements other than cerium and alkaline-earth elements. A mass ratio of platinum with respect to palladium falls within a range of 1/50 to 1/20. The second composite oxide includes zirconium and an element selected from the group consisting of rare-earth elements other than cerium and alkaline-earth elements and has an atomic ratio of cerium with respect to zirconium smaller than that of the first composite oxide.

Abstract: An exhaust gas-purifying catalyst includes first particles of oxygen storage material, second particles of one or more alkaline-earth metal elements and/or compounds thereof interposed between the first particles, and third particles of one or more precious metal elements interposed between the first particles. A spectrum of a first characteristic X-ray intensity for one of the one or more alkaline-earth metal elements and a spectrum of a second characteristic X-ray intensity for one of the one or more precious metal elements that are obtained by performing a line analysis using energy-dispersive X-ray spectrometry along a length of 500 nm have a correlation coefficient ?(AE,PM) of 0.70 or more.

Abstract: An exhaust gas-purifying catalyst includes first particles of oxygen storage material, second particles of one or more alkaline-earth metal elements and/or compounds thereof interposed between the first particles, and third particles of one or more precious metal elements interposed between the first particles. A spectrum of a first characteristic X-ray intensity for one of the one or more alkaline-earth metal elements and a spectrum of a second characteristic X-ray intensity for one of the one or more precious metal elements that are obtained by performing a line analysis using energy-dispersive X-ray spectrometry along a length of 500 nm have a correlation coefficient ?(AE,PM) of 0.70 or more.

Abstract: An exhaust gas-purifying catalyst includes first particles of oxygen storage material, second particles of one or more acidic oxides interposed between the first particles, and third particles of one or more precious metal elements interposed between the first particles, wherein a spectrum of a characteristic X-ray intensity for one of constituent elements of the acidic oxide(s) other than oxygen and a spectrum of a characteristic X-ray intensity for one of the precious metal element(s) that are obtained by performing a line analysis using energy-dispersive X-ray spectrometry along a length of 500 nm have a correlation coefficient of 0.70 or more.

Abstract: An exhaust gas-purifying catalyst includes first particles of oxygen storage material, second particles of one or more rare-earth elements other than cerium and/or compounds thereof interposed between the first particles, and third particles of one or more precious metal elements interposed between the first particles, wherein a spectrum of a characteristic X-ray intensity for one of the rare-earth element(s) and a spectrum of a characteristic X-ray intensity for one of the precious metal element(s) that are obtained by performing a line analysis using energy-dispersive X-ray spectrometry along a length of 500 nm have a correlation coefficient of 0.68 or more.

Abstract: An exhaust gas purifying catalyst exhibiting high purification performance in the Hot range is provided. The exhaust gas purifying catalyst has a catalyst substrate and a catalyst coating layer formed on the catalyst substrate. The catalyst coating layer has a layered structure including an inside layer a containing the component (a-1) and the component (a-2) described below, and an outside layer b containing the component (b-1) and the component (b-2) described below. Component (a-1) and component (b-1): noble metals. Component (a-2): a compound oxide of (i) Ce, (ii) Zr and (iii) an element selected from the group consisting of rare earth elements, alkaline earth elements and Y, having a ratio of (ii) to (i) within the range of more than 40/100 but not more than 100/2 in terms of the weight ratio between CeO2 and ZrO2.

Abstract: A high NOx-purifying performance at high temperature conditions is achieved with a small amount of precious metal used. An exhaust gas-purifying catalyst includes a substrate, a lower layer formed on the substrate and including a first composite oxide, palladium and platinum, and an upper layer formed on the lower layer and including a second composite oxide and rhodium. The first composite oxide includes cerium, zirconium, and an element selected from the group consisting of rare-earth elements other than cerium and alkaline-earth elements. A mass ratio of platinum with respect to palladium falls within a range of 1/50 to 1/20. The second composite oxide includes zirconium and an element selected from the group consisting of rare-earth elements other than cerium and alkaline-earth elements and has an atomic ratio of cerium with respect to zirconium smaller than that of the first composite oxide.

Abstract: An exhaust gas purifying catalyst exhibiting high purification performance in the Hot range is provided. The exhaust gas purifying catalyst has a catalyst substrate and a catalyst coating layer formed on the catalyst substrate. The catalyst coating layer has a layered structure including an inside layer a containing the component (a-1) and the component (a-2) described below, and an outside layer b containing the component (b-1) and the component (b-2) described below. Component (a-1) and component (b-1): noble metals. Component (a-2): a compound oxide of (i) Ce, (ii) Zr and (iii) an element selected from the group consisting of rare earth elements, alkaline earth elements and Y, having a ratio of (ii) to (i) within the range of more than 40/100 but not more than 100/2 in terms of the weight ratio between CeO2 and ZrO2.

Abstract: An exhaust gas-purifying catalyst includes a zeolite and a perovskite composite oxide containing palladium placed at its B site.

Abstract: The present invention relates to a catalyst for purifying exhaust gases emitted from the internal combustion engines. The exhaust-gas-purifying catalyst in this invention, comprising: a catalyst support substrate and a plurality of catalyst layers formed on a surface of the catalyst support substrate and having an exterior-surface layer for forming a surface of the plural catalyst layers, and the exterior-surface layer including a loading layer formed by fireproof inorganic oxide; at least one catalytic metal selected from the group consisting of platinum, palladium and rhodium, and supported on the loading layer; stabilized zirconia loaded on the loading layer; and cerium-zirconium composite oxide loaded on the loading layer, and the stabilized zirconia including zirconia and oxide formed by at least one additive member selected from the group consisting of yttrium, neodymium, praseodymium and lanthanum.

Abstract: An exhaust gas-purifying catalyst includes a zeolite and a perovskite composite oxide containing palladium placed at its B site.