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Título del libro: Clusters And Nano-Assemblies: Physical And Biological Systems: Richmond, Virginia, U.S.A., 10-13 November, 2003
Título del capítulo: Ceria-zirconia-alumina mixed oxides prepared by the organic-free sol-gel technique

Autores UNAM:
VITALI PETRANOVSKI AFANASIEVNA; SERGIO FUENTES MOYADO;
Autores externos:

Idioma:
Inglés
Año de publicación:
2005
Resumen:

The structural composition and the cause of the thermal stability of the obtained structure in the Ce:Zr:A1 (7.5:7.5:85 molar ratio) oxides nanosystem, prepared by the organic-free sol-gel technique were investigated by XRD, FTIR and XPS. According to the XRD analysis, the Ce:Zr:A1 sample calcined at 1100°C in air, presents a nanosystem with dispersion of C-ZrxCe1_x02 S.S.(~10 nm) nanoparticles in nanocrystalline ?-Al203 (-4 nm) matrix. This system remained stable during further heating up to 1200°C during 8 h in air. A strong chemical interaction between the components of ceria-zirconia nanoparticles on the phase boundary with alumina matrix with formation of charge transfer complexes [Zrn+d - O - A1m-d] and [Cen+d - O - A1m+d] could explain the quenching of nanocrystalline state in this system, that "freeze" crystallization even at high temperatures. © 2005 by World Scientific Publishing Co. Pte. Ltd. All rights reserved.


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