Abstract: The present disclosure provides an exhaust gas purification catalyst improved in OSC performance while maintaining an exhaust gas purification performance, which comprises a substrate and at least one catalyst layer formed on the substrate, wherein an uppermost catalyst layer contains a catalyst metal, a first OSC material having a pyrochlore structure, and a second OSC material having a higher oxygen storage/release rate than the first OSC material, wherein the uppermost catalyst layer consists of an upstream catalyst layer and a downstream catalyst layer, and wherein a proportion of a mass of the second OSC material based on a total mass of the first OSC material and the second OSC material is in a specific range in each of the upstream catalyst layer and the downstream catalyst layer.

Abstract: Provided is an exhaust gas purification catalyst capable of reducing a noble metal amount while maintaining a catalyst performance, which comprises a substrate and at least three catalyst coating layers formed on the substrate, the first and third catalyst coating layers contain Pd as a catalyst metal and are formed in a range of a predetermined length from an upstream end surface in an exhaust gas flow direction, and the second catalyst coating layer contains Rh as a catalyst metal and is formed in a range of a predetermined length from a downstream end surface in the exhaust gas flow direction.

Abstract: Provided is an exhaust gas purification device that allows improving an exhaust gas purification performance. An exhaust gas purification device of the present disclosure includes a substrate and a catalyst layer disposed on the substrate. The catalyst layer contains a porous carrier, a catalytic metal that is supported by the porous carrier and belongs to platinum group, an alkaline earth metal supported by the porous carrier, and an alkaline earth metal not supported by the porous carrier. At least a part of the alkaline earth metal supported by the porous carrier is supported inside the porous carrier.

Abstract: Provided is an exhaust gas purification catalyst having an improved catalyst performance while securing an OSC in an air-fuel ratio (A/F) rich atmosphere where HC poisoning is likely to occur. The present disclosure relates to an exhaust gas purification catalyst including a substrate and a catalyst coating layer coated on the substrate. The catalyst coating layer has an upstream coat layer formed from an end portion in an upstream side with respect to an exhaust gas flow direction in the exhaust gas purification catalyst and a downstream coat layer formed from an end portion in a downstream side with respect to the exhaust gas flow direction in the exhaust gas purification catalyst. The downstream coat layer includes Rh as a catalytic metal, alumina-ceria-zirconia complex oxide, and alkaline earth metal.

Abstract: The present disclosure provides an exhaust gas purification catalyst having improved durability, which comprises a substrate and a catalyst coat layer formed on the substrate, the catalyst coat layer having a two-layer structure, wherein the catalyst coat layer includes an upstream portion on an upstream side and a downstream portion on a downstream side in an exhaust gas flow direction, and a part or all of the upstream portion is formed on a part of the downstream portion, wherein the downstream portion contains Rh fine particles, and 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 ? of the particle size of 0.8 nm or less.

Abstract: Methods for exhaust gas purification, including the steps of: attaching an exhaust gas purification catalyst to an exhaust system of an internal combustion engine, and supplying an exhaust gas to the exhaust gas purification catalyst, where the exhaust gas purification catalyst includes an upper layer containing first carrier particles which are particles of an inorganic oxide and rhodium, and a lower layer containing second carrier particles which are particles of an inorganic oxide, the upper layer includes a rhodium-rich portion near the surface of the upper layer on the upstream side of the exhaust gas flow, and the existence range of the rhodium-rich portion is in a range of greater than 50% to 80% of the length of the upper layer from a downstream side end of an exhaust gas flow and of less than 20 ?m in the depth direction from an outermost surface of the upper layer.

Abstract: Methods for exhaust gas purification, including the steps of: attaching an exhaust gas purification catalyst to an exhaust system of an internal combustion engine, and supplying an exhaust gas to the exhaust gas purification catalyst, where the exhaust gas purification catalyst includes an upper layer containing first carrier particles which are particles of an inorganic oxide and rhodium, and a lower layer containing second carrier particles which are particles of an inorganic oxide, the upper layer includes a rhodium-rich portion near the surface of the upper layer on the upstream side of the exhaust gas flow, and the existence range of the rhodium-rich portion is in a range of greater than 50% to 80% of the length of the upper layer from a downstream side end of an exhaust gas flow and of less than 20 ?m in the depth direction from an outermost surface of the upper layer.

Abstract: The present disclosure provides an exhaust gas purification catalyst having an improved Rh activation, which comprises a substrate and a catalyst coat layer formed on the substrate, the catalyst coat layer having a two-layer structure, wherein the catalyst coat layer includes an upstream portion on an upstream side and a downstream portion on a downstream side in an exhaust gas flow direction, and a part or all of the upstream portion is formed on a part of the downstream portion, wherein the upstream portion contains Rh fine particles and Pt, 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 ? of the particle size of 0.8 nm or less, and wherein the downstream portion contains Rh.

Abstract: The present disclosure provides the exhaust gas purification catalyst with the improved purification performance under the high Ga condition and the transient state in which an A/F repeats rich and lean phases. The present disclosure relates to an exhaust gas purification catalyst comprising a catalyst coating layer on a substrate, the catalyst coating layer containing a noble metal, a composite oxide containing cerium oxide and zirconium oxide, and a composite oxide containing aluminum oxide, wherein in the catalyst coating layer: an average thickness of the coating layer is in a range from 20 ?m to 100 ?m; a porosity measured by a weight-in-water method is in a range from 50% by volume to 80% by volume; and high-aspect-ratio pores having an aspect ratio of 5 or more account for 0.

Abstract: The present disclosure provides an exhaust gas purification catalyst improved in OSC performance while maintaining an exhaust gas purification performance, which comprises a substrate and at least one catalyst layer formed on the substrate, wherein an uppermost catalyst layer contains a catalyst metal, a first OSC material having a pyrochlore structure, and a second OSC material having a higher oxygen storage/release rate than the first OSC material, wherein the uppermost catalyst layer consists of an upstream catalyst layer and a downstream catalyst layer, and wherein a proportion of a mass of the second OSC material based on a total mass of the first OSC material and the second OSC material is in a specific range in each of the upstream catalyst layer and the downstream catalyst layer.

Abstract: The exhaust gas purification catalyst device includes an upper layer which includes first carrier particles and rhodium, and a lower layer which includes second carrier particles, and the upper layer includes a rhodium enriched area in the range a, from the upstream end in the exhaust gas flow to 50% of the upper layer length, and a range b from the upper layer top surface to 18 ?m in the depth direction. The rhodium enriched area contains at least 50% and less than 100% of all the rhodium in the upper layer.

Abstract: An exhaust gas purification device includes a substrate including an upstream end and a downstream end and having a length Ls; a first containing Pd particles, extending between the upstream end and a first position, and being in contact with the substrate; a second containing Rh particles, extending between the downstream end and a second position, and being in contact with the substrate; and a third catalyst layer containing Rh particles, extending between the upstream end and a third position, and being in contact with at least the first catalyst layer, wherein an average of a Rh particle size distribution is from 1.0 to 2.0 nm, and a standard deviation of the Rh particle size distribution is 0.8 nm or less in each of the second catalyst layer and the third catalyst layer.

Abstract: Methods for exhaust gas purification, including the steps of: attaching an exhaust gas purification catalyst to an exhaust system of an internal combustion engine, and supplying an exhaust gas to the exhaust gas purification catalyst, where the exhaust gas purification catalyst includes an upper layer containing first carrier particles which are particles of an inorganic oxide and rhodium, and a lower layer containing second carrier particles which are particles of an inorganic oxide, the upper layer includes a rhodium-rich portion near the surface of the upper layer on the upstream side of the exhaust gas flow, and the existence range of the rhodium-rich portion is in a range of greater than 50% to 80% of the length of the upper layer from a downstream side end of an exhaust gas flow and of less than 20 ?m in the depth direction from an outermost surface of the upper layer.

Abstract: Provided is an exhaust gas purification catalyst having an improved catalyst performance while securing an OSC in an air-fuel ratio (A/F) rich atmosphere where HC poisoning is likely to occur. The present disclosure relates to an exhaust gas purification catalyst including a substrate and a catalyst coating layer coated on the substrate. The catalyst coating layer has an upstream coat layer formed from an end portion in an upstream side with respect to an exhaust gas flow direction in the exhaust gas purification catalyst and a downstream coat layer formed from an end portion in a downstream side with respect to the exhaust gas flow direction in the exhaust gas purification catalyst. The downstream coat layer includes Rh as a catalytic metal, alumina-ceria-zirconia complex oxide, and alkaline earth metal.

Abstract: The present disclosure relates to an exhaust gas control catalyst including a base and a catalyst coating layer having a two-layer structure on the base. The catalyst coating layer includes a lower layer on the base, and an upper layer on the lower layer. The upper layer of the catalyst coating layer contains Rh particles in which a mean particle diameter measured by observation using a transmission electron microscope is 1.0 nm or more and 2.0 nm or less and a particle-diameter standard deviation ? is 0.8 nm or less. A length of the upper layer from an end face on a downstream side in an exhaust gas flow direction falls within a range of 70% or more and 100% or less of a total length of the base.

Abstract: 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 ? 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.

Abstract: Provided is an exhaust gas purification device that allows improving an exhaust gas purification performance. An exhaust gas purification device of the present disclosure includes a substrate and a catalyst layer disposed on the substrate. The catalyst layer contains a porous carrier, a catalytic metal that is supported by the porous carrier and belongs to platinum group, an alkaline earth metal supported by the porous carrier, and an alkaline earth metal not supported by the porous carrier. At least a part of the alkaline earth metal supported by the porous carrier is supported inside the porous carrier.

Abstract: An exhaust gas purification device includes a substrate including an upstream end and a downstream end, the substrate having a length Ls between the upstream end and the downstream end; a first catalyst layer containing first catalyst particles, extending across a first region, and being in contact with the substrate, the first region extending between the upstream end and a first position, the first position being at a first distance La from the upstream end toward the downstream end; and a second catalyst layer containing second catalyst particles, extending across a second region, and being in contact with the substrate, the second region extending between the downstream end and a second position, the second position being at a second distance Lb from the downstream end toward the upstream end. The first catalyst layer has an inner surface defining macropores.

Abstract: The exhaust gas cleaning catalyst according is provided with a substrate and a catalyst coat layer formed on a surface of the substrate. The catalyst coat layer is formed as a laminate structure having an upper layer and a lower layer. The upper layer is a Pd-free layer that does not contain Pd, and the lower layer is a Pd-containing layer. In addition, when a region of the lower layer that corresponds to 20% of the length of the exhaust gas cleaning catalyst from the exhaust gas inlet side end towards the exhaust gas outlet side of the exhaust gas cleaning catalyst is divided into four equal regions to be each 5% of the length, the relationship A>B>C is satisfied, where A, B, and C represents the Pd content in the first, second, and third region respectively.

Abstract: An exhaust gas purification device includes a substrate including an upstream end and a downstream end and having a length Ls; a first containing Pd particles, extending between the upstream end and a first position, and being in contact with the substrate; a second containing Rh particles, extending between the downstream end and a second position, and being in contact with the substrate; and a third catalyst layer containing Rh particles, extending between the upstream end and a third position, and being in contact with at least the first catalyst layer, wherein an average of a Rh particle size distribution is from 1.0 to 2.0 nm, and a standard deviation of the Rh particle size distribution is 0.8 nm or less in each of the second catalyst layer and the third catalyst layer.