Preparation and Properties of Nanostructured Ceria-Zirconia Powders

摘要

Nanostructured cerium oxide is used as an oxygen storage component in 3-way catalytic converters but its effectiveness in this role declines in service due to the reduction of specific surface area by crystal growth at normal catalyst operating temperatures. Ceria-zirconia mixed oxide powders were prepared which demonstrated improved resistance to crystal growth at high temperatures. Compositions with Ce/Zr ratios of 0.75/0.25 and 0.5/0.5 were produced for comparison with pure ceria. The powders were produced from aqueous solution by a two-stage precipitation process using hydrogen peroxide and ammonium hydroxide.