This invention aims at providing a catalyst body exhibiting a lower
degradation of a catalyst due to thermal durability and capable of
keeping higher catalyst performance for a long time. A catalyst component
such as Pt is directly supported by Zr, W, etc, replacing elements inside
a support such as Al of cordierite to provide a catalyst body without
forming a coating layer. A combination of the catalyst component and the
element inside the support is selected so that support strength is
greater than 5 eV by simulation using a density functional method.
Coarsening of catalyst particles can be suppressed and a high-performance
catalyst body excellent in thermal durability can be obtained.