Post-graduate theses
Current Record: 4837 of 6695
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Identifier |
000383407 |
Title |
Ανάπτυξη και χαρακτηρισμός μεσοδομημένων οξο-βαναδο-βολφραμικών πλεγμάτων.Εφαρμογές στην οξειδωτική μετατροπή οργανικών συμπλόκων |
Author
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Σκλήρη, Ευαγγελία
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Thesis advisor
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Αρματάς, Γεράσιμος
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Reviewer
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Λυκάκης, Ιωάννης
Βαμβακάκη, Μαρία
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Abstract |
Ordered mesoporous tungsten(VI) oxide – vanadium oxide (V2O5) nanocomposite frameworks have been successfully prepared via a nanocasting method, using NH2-functionalized mesoporous SBA-15 silica as a hard template. These heterostructures possess a mesoscopic order of discernible domains of parallel-arranged uniform nanorods and exhibit relatively large internal surface area and quite narrow pore size distribution. The chemical composition and mesoporous structure of as-prepared materials were characterized by using various techniques like X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray (EDS), ultraviolet-visible (UV-vis) and Raman spectroscopy and nitrogen porosimetry. The integration of regular porosity and WO3–V2O5 composition makes these materials highly promising for applications in oxidation catalysis. Our results indicated that the inclusion of V2O5 compounds in mesoporous structure has a beneficial effect on the catalytic activity of these materials. Although WO3 alone show little catalytic activity, the WO3–V2O5 heterostructures exhibit high activity in hydrogen peroxide mediated oxidation of 1-phenylethanol under mild conditions. Indeed, the oxidation activity of WO3–V2O5 composites is strongly related to the chemical composition of composite structure, with particular relevance of the V2O3 content. Furthermore, the mesoporous WO3–V2O5 catalysts demonstrated remarkable activity and stability for the oxidation of selected para–substituted benzyl alcohols, giving good-to-high yields (ca. 63 – 82%) within a short reaction time (0.5 – 1 h).
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Language |
Greek |
Subject |
Κατάλυση |
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Μεσοπορώδη υλικά |
Issue date |
2014-03-28 |
Collection
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School/Department--School of Sciences and Engineering--Department of Materials Science and Technology--Post-graduate theses
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Type of Work--Post-graduate theses
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Permanent Link |
https://elocus.lib.uoc.gr//dlib/e/7/3/metadata-dlib-1399527428-60095-32564.tkl
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Views |
290 |