Structure, morphology and reducibility of ceria-doped zirconia

Abstract Zr 1-x Ce x O x has been prepared by hydrolysis, in neutral medium, starting from rough ZrO 2 and CeO 2 materials as simple and cheaper synthesis method compared to sol-gel routes. The oxy-hydroxide precursors thus obtained were calcined under air at 450 °C, 900 °C and 1200 °C. The impact of those thermal treatments on the structure, texture and related redox properties has been investigated. Higher specific surface area than those observed on ceria were observed after calcination at low temperature, i.e., 450 °C. Above that temperature thermal sintering occurs having a detrimental effect on the specific surface area related to crystal growth more accentuated on CeO 2 . The formation of several Zr Ce mixed oxide phases formed by incorporation and substitution of Zr in the structure of ceria was characterized. A complete loss of specific surface area is noticeable after calcination at 1200 °C. XRD and SEM analysis revealed the formation of two mixed oxides structure, i.e. Ce 2 Zr 2 O 7.04 and Ce 2 Zr 2 O 7 corresponding to different redox behavior evidenced from H 2 -TPR experiments.