Abstract: Provided is an exhaust gas purification catalyst providing a catalyst performance and an OSC performance at the same time even at low temperature. 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 includes a first catalyst coating layer containing Pd and/or Pt and a second catalyst coating layer containing Rh. The first catalyst coating layer is formed from an end portion in an upstream side with respect to an exhaust gas flow direction in the exhaust gas purification catalyst. The second catalyst coating layer includes an upstream coating layer and a downstream coating layer. Rh in the upstream coating layer and the downstream coating layer are supported on specific carrier particles. Further, a particle diameter of Rh is controlled.

Abstract: Provided is an exhaust gas purification catalyst having a catalyst performance and an OSC performance in a compatible manner in an air-fuel ratio (A/F) rich atmosphere where HC poisoning is likely to occur. The exhaust gas purification catalyst includes a substrate and a catalyst coating layer coated on the substrate. The catalyst coating layer includes a first catalyst coating layer containing Pd and/or Pt as a catalyst metal and a second catalyst coating layer containing Rh as a catalyst metal. The first catalyst coating layer is formed from an end portion in an upstream side with respect to an exhaust gas flow direction in the exhaust gas purification catalyst. The second catalyst coating layer includes a high specific surface area OSC material having a specific surface area of more than 40 m2/g, a medium specific surface area OSC material having a specific surface area of 4 m2/g to 40 m2/g, and a low specific surface area OSC material having a specific surface area of less than 4 m2/g.

Abstract: An exhaust gas purification catalyst device having a base material, an upstream-side lower coat layer, an upstream-side upper coat layer, a downstream-side lower coat layer, and a downstream-side upper coat layer, the exhaust gas purification catalyst device satisfying conditions (i) and (ii). (i) The concentration of Pt and/or Pd in the upstream-side upper coat layer and the downstream-side lower coat layer is greater than the concentration of Pt and/or Pd in the upstream-side lower coat layer, and is greater than the concentration of Pt and/or Pd in the downstream-side upper coat layer. (ii) The concentration of Rh in the upstream-side lower coat layer and the downstream-side upper coat layer is greater than the concentration of Rh in the upstream-side upper coat layer, and is greater than the concentration of Rh in the downstream-side lower coat 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: 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: Provided is an exhaust gas purification catalyst body that can improve exhaust gas purification performance while maintaining favorable PM collection performance. The exhaust gas purification catalyst body includes a base of a wall flow structure having an inlet side cell, an outlet side cell, and porous partition wall, and a catalyst layer that is formed in the partition wall that is in contact with the inlet side cell or the outlet side cell. The catalyst layer is formed in a region of at least 50% of the thickness of the partition wall from a surface of the partition wall, and held on the surface of internal pores in the partition wall in the region.

Abstract: Provided is an exhaust gas purification catalyst body that can improve exhaust gas purification performance while maintaining favorable PM collection performance. The exhaust gas purification catalyst body includes a base of a wall flow structure having an inlet side cell, an outlet side cell, and porous partition wall, and a catalyst layer that is formed in the partition wall that is in contact with the inlet side cell or the outlet side cell. The catalyst layer is formed in a region of at least 50% of the thickness of the partition wall from a surface of the partition wall, and held on the surface of internal pores in the partition wall in the region.