Exhaust gas purification device and method for manufacturing exhaust gas purification device

An exhaust gas purification device comprising:

• a substrate including an upstream end through which an exhaust gas is introduced into the device and a downstream end through which the exhaust gas is discharged from the device, the substrate having a length (Ls) between the upstream end and the downstream end;
• a first catalyst layer extending across a first region, the first region extending between the downstream end and a first position, the first position being at a first distance (La) from the downstream end toward the upstream end, the first catalyst layer containing a first rhodium-containing catalyst and a first cerium-containing oxide, the first rhodium-containing catalyst containing a first metal oxide carrier and first rhodium particles supported on the first metal oxide carrier, a mean of a particle size distribution of the first rhodium particles being from more than 4 nm and equal to or less than 14 nm;
• a second catalyst layer extending across a second region, the second region extending between the upstream end and a second position, the second position being at a second distance (Lb) from the upstream end toward the downstream end, the second catalyst layer containing a second rhodium-containing catalyst containing a second metal oxide carrier and second rhodium particles supported on the second metal oxide carrier;
• and
• a third catalyst layer containing palladium particles, the third catalyst layer extending across a third region, the third region extending between the upstream end and a third position, the third position being at a third distance (Lc) from the upstream end toward the downstream end,
• wherein the second catalyst layer is formed on the third catalyst layer, and
• wherein a cerium content in the first catalyst layer based on a volume capacity of the substrate in the first region is higher than a cerium content in the second catalyst layer based on a volume capacity of the substrate in the second region.