Abstract: A series of oxygen-deficient perovskite-supported palladium
catalysts were prepared by the "solid phase crystallization" (spc) method and
investigated with XRD, TPR, TPD, TEM, XPS, BET analysis and CO oxidation. It
was found that Pd/perovskite catalysts synthesized by the spc method were more
active for CO oxidation than the calcined LaCo_{0.95}
Pd_{0.05}O_3, where Pd dispersed in the
solid solution. H_2-reducing treatment in the spc method
could yield not only high-dispersed fine Pd particles on the perovskite surface
but also oxygen-deficient structure. In these perovskite-supported Pd
catalysts, oxygen vacancies adsorbed, activated and supplied oxygen to the
active Pd sites, where the oxidation occurred with adsorbed CO. The high
activities were due to the cooperative action of Pd and oxygen vacancies.