EXAFS study of the Fex/ZrO2 composite nanomaterials obtained by sol-gel synthesis
The local Zr and Fe arrangements in the nanocomposite system Fex/ZrO2 (x=0-0.2) obtained by sol-gel method were studied by EXAFS. The phase composition was found to vary significantly on iron loading. For the samples calcined at 500 or 600°C, at x≤0.01, the formed ZrO2 is a mixture of monoclinic and...
| Autores: | , , , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2001 |
| País: | España |
| Institución: | Universidad de Sevilla (US) |
| Repositorio: | idUS. Depósito de Investigación de la Universidad de Sevilla |
| OAI Identifier: | oai:idus.us.es:11441/63510 |
| Acceso en línea: | http://hdl.handle.net/11441/63510 https://doi.org/10.1107/S0909049501000875 |
| Access Level: | acceso abierto |
| Palabra clave: | EXAFS Zirconia Surface Nanoparticles |
| Sumario: | The local Zr and Fe arrangements in the nanocomposite system Fex/ZrO2 (x=0-0.2) obtained by sol-gel method were studied by EXAFS. The phase composition was found to vary significantly on iron loading. For the samples calcined at 500 or 600°C, at x≤0.01, the formed ZrO2 is a mixture of monoclinic and tetragonal structures. Only tetragonal structure is revealed at x≥0.05 with the exception of Fe0.2/ZrO2, calcined at 500°C, where new non-typically short Zr-Zr distances (3.29, 3.43Å) were observed. At low iron loading (less than one monolayer) Fe3+ ions were found to localize within the pre-surface layers of ZrO2 nanoparticles showing property of isolated ions. For greater Fe loading, iron exhibits either two-dimensional layer structure or two-phase system. |
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