An exhaust gas purification catalyst device having a substrate and one or more catalytic noble metals supported on the substrate. The substrate has a plurality of cells partitioned by a porous wall 1 and includes ceria-zirconia compound oxide particles. A specific noble metal that is one of the one or more catalytic noble metals satisfies both the following requirements (1) and (2): (1) the noble metal 50% support depth for the specific noble metal is 30% or less of the distance from the surface of the porous wall 1 to the center of the interior of the porous wall 1, and (2) the noble metal 90% support depth for the specific noble metal is 35% or more of the distance from the surface of the porous wall 1 to the center of the interior of the porous wall 1.

An exhaust gas purification catalytic device includes: a substrate; at least one type of noble-metal catalyst that is supported on the substrate; and a coating layer on the surface of the substrate. The substrate includes a plurality of cells which are demarcated by porous walls. The substrate and the coating layer each include ceria-zirconia composite oxide particles.

Provided are an exhaust gas purifying catalyst structure that inhibits foil elongation and improves structural durability and a production method therefor. The exhaust gas purifying catalyst structure has a metal support configured by using an mantle and a metal foil provided in the mantle and forming an exhaust gas flow path, and a catalyst layer provided on a surface forming the flow path of the metal foil, wherein the catalyst layer contains a noble metal, an OSC material containing cerium and a rare earth element other than cerium (non-Ce rare earth element), and alumina, and a content of the non-Ce rare earth element with respect to 100% by mass of the catalyst layer is 2.52% by mass or more and 4.62% by mass or less in terms of an oxide.

The present disclosure provides an exhaust gas purification catalyst having an improved low-temperature activity, which comprises a substrate and a catalyst coat layer formed on the substrate, wherein the catalyst coat layer contains Rh fine particles and a promoter comprising a Ce—Zr-based composite oxide and a Zr-based composite oxide not containing cerium oxide, wherein the Rh fine particles have an average particle size measured by a transmission electron microscope observation of 1.0 nm or more to 2.0 nm or less, and a standard deviation σ of the particle size of 0.8 nm or less, and wherein the Rh fine particles are supported on each of the Ce—Zr-based composite oxide and the Zr-based composite oxide not containing cerium oxide.

An improved SCRoF (selective catalytic reduction on filter) device for treating exhaust from an internal combustion engine. The filter has numerous entry and exit channels. Exhaust enters the entry channels and flows through side walls into the exit channels. Relative to the exhaust flow path, these side walls are coated on the downstream side with a ceria-based catalyst and on the upstream side with a Cu-zeolite catalyst. This allows the filter to optimally achieve both particulate matter oxidation and NOx reduction, respectively.

An oxygen storage material (OSM) includes a zinc manganese iron oxide (ZMF) and an alkali metal base on the ZMF surface. The ZMF has a spinel structure. The alkali metal containing ZMF can be formed to have a weight percent of alkali metal up to about two percent. The alkali metal carbonate is retained on the ZMF surface upon heating to a temperature greater than 1,000° C. and stabilizes the ZMF to the cycling of an oxygen rich and oxygen lean atmosphere. The OSM additionally catalyzes the oxidation of hydrocarbons and CO and catalyzes the reduction of NO.sub.x for use in catalytic converters.

A substrate (11) of an exhaust gas purification catalyst (10) includes inflow-side cells (21), outflow-side cells (22), and porous partition walls (23) each separating the inflow-side cell and the outflow-side cell. Catalyst portions (14, 15) are provided on surfaces of the partition walls that each face the inflow-side cell and/or surfaces of the partition walls that each face the outflow-side cell. In a cross section vertical to an exhaust gas flow direction, the percentage of the total area of voids, each void satisfying the expression L/{2(πS).sup.1/2}≤1.1, wherein L is the perimeter of the void in the cross section and S is the area of the void in the cross section, is from 3 to 10% based on the apparent area of the catalyst portion present on the partition wall.

A method of manufacturing a catalyst article, the method comprising: providing a complex of a polyamine and a PGM; providing a support material; applying the complex to the support material to form a loaded support material; disposing the loaded support material on a substrate; and heating the loaded support material to form nanoparticles of the PGM on the support material.

The catalyst deterioration detection system 1 comprises an air-fuel ratio detection device 41 detecting an air-fuel ratio of an exhaust gas flowing out from the catalyst 20, an air-fuel ratio control part 71, and a deterioration judgment part 72. The air-fuel ratio control part is configured to perform a lean control making the air-fuel ratio of the inflowing exhaust gas leaner than a stoichiometric air-fuel ratio and a rich control making the air-fuel ratio of the inflowing exhaust gas richer than the stoichiometric air-fuel ratio. The deterioration judgment part is configured to calculate an amplitude of an air-fuel ratio of an exhaust gas flowing out from the catalyst due to the lean control and the rich control based on an output of the air-fuel ratio detection device and judge that the catalyst is deteriorating if the amplitude is equal to or greater than a threshold value.

Disclosed are a cerium-zirconium solid solution and a preparation method therefor and an application thereof, which belong to the field of adsorbing catalyst materials. The cerium-zirconium solid solution includes a cerium-zirconium solid solution phase with a Ce.sup.3+/Ce.sup.4+ molar ratio of 0.05-0.8:1. The cerium-zirconium solid solution phase in the cerium-zirconium solid solution of the present application includes trivalent cerium ions and tetravalent cerium ions in a specific ratio. The cerium-zirconium solid solution has a high oxygen storage and release rate, a high oxygen storage and release capacity, and the cerium-zirconium solid solution during the storage and release of oxygen has a stable structure and good catalytic performance; and the catalyst containing the cerium-zirconium solid solution has good catalytic performance under different fuel ratios.