关键词: Ce0.8Zr0.2O2, 溶胶凝胶法, 共沉淀法, 水热法, 碳烟燃烧

Abstract: A series of Ce0.8Zr0.2O2 catalysts were prepared by citric acid sol-gel method，low temperature co-precipitation method，high temperature co-precipitation method，hydrothermal method and thermal decomposition method. The structures, surface morphologies, oxygen storage capacities, and redox abilities of all catalysts were characterized by XRD, BET, SEM, thermogravimetric analysis, H2-TPR and O2-TPO. Potentials of the catalysts in the soot oxidation were evaluated by TPO analysis. The effects of preparation methods on the performance of catalytic soot combustion were investigated. The results indicate that the cerium zirconium solid solution with cubic fluorite structure is formed in all samples by all of the above methods. Sol-gel method is in favor of oxygen storage capacity and performance improvement; hydrothermal method helps improve the catalyst specific surface area; the catalyst prepared by thermal decomposition method has a flat surface structure which enhances the mechanical strength. However, the catalyst prepared by co-precipitation is poor in oxygen storage capacity and catalytic activity due to the influence of the temperature during the preparation.

Key words: Ce0.8Zr0.2O2, sol-gel, co-precipitation, hydrothermal, soot combustion