Chapter 5.1 Characterization of V2O5/TiO2 catalysts by solid state NMR of 51V
| Autor: | C. Femandez, M. Guelton |
|---|---|
| Přispěvatelé: | Laboratoire de dynamique et structure des matériaux moléculaires (LDSMM), Université de Lille, Sciences et Technologies-Université du Littoral Côte d'Opale (ULCO)-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 1994 |
| Předmět: |
Analytical chemistry
Vanadium chemistry.chemical_element 02 engineering and technology General Chemistry Nuclear magnetic resonance spectroscopy [CHIM.CATA]Chemical Sciences/Catalysis [CHIM.MATE]Chemical Sciences/Material chemistry 010402 general chemistry 021001 nanoscience & nanotechnology Heterogeneous catalysis 01 natural sciences Catalysis 0104 chemical sciences chemistry Solid-state nuclear magnetic resonance Octahedron Magic angle spinning 0210 nano-technology Spinning ComputingMilieux_MISCELLANEOUS |
| Zdroj: | Catalysis Today Catalysis Today, Elsevier, 1994, 20 (1), pp.77-86. ⟨10.1016/0920-5861(94)85017-8⟩ |
| ISSN: | 0920-5861 |
| DOI: | 10.1016/0920-5861(94)85017-8⟩ |
| Popis: | The catalysts V2O5 (8%)/TiO2 (EL10V8) andV2O5/TiO2 (EL 10V1) have been studied by solid state 51V NMR spectroscopy using both wide-line (static samples) and MAS conditions (magic angle spinning samples). The experimental results, obtained using three different spectrometers and three experimental methods, are discussed and analysed. It is demonstrated that the quadrupolar echo method allows a better detection of the vanadium nuclei than the single pulse method if only a wide-line signal analysis is desired. It is also shown that the MAS method can detect small changes in the chemical shift of different species; however, in this case, very high spinning frequencies are necessary in order to separate the peaks from their spinning sidebands. In both samples, all experiments reveal that the majority of the surface vanadium atoms are in a distorted octahedral environment similar to that of the vanadium in V2O5. Moreover, the use of high speed magic angle spinning shows that a small quantity of another vanadium species is present on EL10V8 with a structure also nearly similar to V2O5. |
| Databáze: | OpenAIRE |
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