Whitening and Characterization of Calcia-doped Ceria Nanoparticles

Abstract

The changes in color and oxidation catalytic activity by heat treatment of ceria nanoparticles were investigated. Although as-prepared ceria powder was yellow, the powder calcined above 700°C was white and the oxidation catalytic activity greatly decreased. TG analysis of prepared ceria nanoparticles showed ca. 4% of weight loss from 200 to 700°C, while density of ceria particles increased with temperature up to 700°C. These results suggested that the change in colar of ceria particles with calcination was caused by the decrease of the lattice defect.