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arXiv · 1503.01963

Structural studies of mesoporous ZrO$_{2}$-CeO$_{2}$ and ZrO$_{2}$-CeO$_{2}$/SiO$_{2}$ mixed oxides for catalytical applications

R. Bacani·T. S. Martins·D. G. Lamas·M. C. A. Fantini
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Abstract

In this work the synthesis of ZrO$_{2}$-CeO$_{2}$ and ZrO$_{2}$-CeO$_{2}$/SiO$_{2}$ were developed, based on the process to form ordered mesoporous materials such as SBA-15 silica. The triblock copolymer Pluronic P-123 was used as template, aiming to obtain crystalline single phase walls and larger specific surface area, for future applications in catalysis. SAXS and XRD results showed a relationship between ordered pores and the material crystallization. 90% of CeO$_{2}$ leaded to single phase homogeneous ceria-zirconia solid solution of cubic fluorite structure (Fm$\bar{3}$m). The SiO$_{2}$ addition improved structural and textural properties as well as the reduction behavior at lower temperatures, investigated by XANES measurements under H$_{2}$ atmosphere.

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R. Bacani, T. S. Martins, D. G. Lamas, M. C. A. Fantini. 2016-01-12. Structural studies of mesoporous ZrO$_{2}$-CeO$_{2}$ and ZrO$_{2}$-CeO$_{2}$/SiO$_{2}$ mixed oxides for catalytical applications. https://doi.org/10.1016/j.jallcom.2016.01.213

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