| abstract |
The present invention provides an exhaust gas purification catalyst including an alkaline-earth metal carried on a porous carrier in a highly dispersed state. The catalyst layer of the exhaust gas purification catalyst provided by the present invention has an alkaline-earth metal carrying region including a porous carrier, Pt, and a sulfuric acid salt of at least one alkaline-earth metal carried on the porous carrier, characterized in that a value of R Ae/Pt is 0.5 or more, where R Ae/Pt represents the Pearson's correlation coefficient calculated using α and β in each pixel obtained by, for a cross section of the region, performing the area analysis by FE-EPMA under the conditions of: pixel size 0.34 µm × 0.34 µm; and number of measured pixels 256 × 256; and measuring an intensity (α: cps) of a characteristic X ray of an element (Ae) of the alkaline-earth metal and an intensity (β: cps) of a characteristic X ray of Pt for each pixel. |