Structural Investigation of Mixed Nitrided Galloaluminophosphates 'AlGaPON' by EELS, XAS, and XPS Spectroscopies
| Autor: | S. Delsarte, A.-M. Flank, V. Serin, F. Villain, P. Grange |
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| Rok vydání: | 2002 |
| Předmět: |
X-ray absorption spectroscopy
Absorption spectroscopy Extended X-ray absorption fine structure Chemistry Electron energy loss spectroscopy Analytical chemistry Condensed Matter Physics XANES Electronic Optical and Magnetic Materials Inorganic Chemistry X-ray photoelectron spectroscopy Materials Chemistry Ceramics and Composites Physical and Theoretical Chemistry Spectroscopy Nitriding |
| Zdroj: | Journal of Solid State Chemistry. 163:163-177 |
| ISSN: | 0022-4596 |
| DOI: | 10.1006/jssc.2001.9389 |
| Popis: | Amorphous nitrided galloaluminophosphates "AlGaPON" catalysts with nitrogen contents varying from 0 to 23.3 wt% N were obtained by nitriding an Al0.5Ga0.5PO4 precursor under ammonia flow at 750degreesC in a tubular furnace. The structural changes induced by this treatment were investigated by electron energy loss spectroscopy (EELS), X-ray absorption spectroscopy (XAS), and X-ray photoelecton spectroscopy (XPS). XANES and XPS results indicate that the first-coordination spheres of P, Ga, and Al atoms are modified by nitridation. In particular, the comparison of the P XANES spectra recorded on "AlGaPON" and on a PON phosphorus oxynitride (reference of mixed PO2,N-2, tetrahedra) reveals that mainly PO2,N-2, tetrahedra are present in highly nitrided samples. Moreover, the replacement of oxygen by nitrogen probably concerned P-O-Ga bonds rather than P-O-Al. EELS investigation reveals that the precursor is homogeneous at the used probe scale, but indicates that nitridation is accompanied by a loss of homogeneity of the material. (C) 2002 Elsevier Science. |
| Databáze: | OpenAIRE |
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