Abstract
The solid solution of CeO2-ZrO2 is used widely as a three-way catalyst for an automobile as an oxygen storage material. A reduction treatment of this solid solutions with around Ce/Zr=50/50 at high temperature, especially above 1473K, gives the CeO2-ZrO2 solid solution with better oxygen storage/release property. It was revealed that the improvement of oxygen absorption/release was due to the ordered arrangement of Ce and Zr ion by this treatment. The role of the ordered arrangement of Ce and Zr ions in the oxygen storage property was studied by measurement of the oxygen absorption behavior and by observation of crystal structure change. The effect of the formation of the ordered arrangement on oxygen release/storage property can be explained on the basis of Zr coordination polyhedron in CeO2-ZrO2 solid solution.
