Post-graduate theses
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Identifier |
000426152 |
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Title |
Οργανωμένες Μεσοπορώδεις Ετεροδομές Zr1-xCexO2: Σύνθεση, Χαρακτηρισμός και Εφαρμογή στην Φωτοκαταλυτική Οξείδωση Άρυλο Αλκοολών |
Author
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Γκότσι, Εσμεράλντα
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Thesis advisor
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Αρματάς, Γεράσιμος
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Reviewer
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Κοπιδάκης, Γεώργιος
Ρεμεδιάκης, Ιωάννης
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Abstract |
In this thesis work, we present the synthesis of high-surface area mesoporous materials of ZrO2–CeO2 composition. A series of mesoporous ZrO2-based CeO2 nanocomposite frameworks (Ce/ZrO2) has been successfully prepared through a polymer-assisted sol-gel copolymerization route. The pore walls of these heterostructures consist of nanocrystalline tetragonal ZrO2 and CeO2 components with different CeO2 loadings, i.e. 2, 3, 5 and 10 wt %. Structural characterization by X-ray diffraction (XRD) and N2 physisorption measurements indicated a well-crystalline structure with large internal BET (Brunauer, Emmett and Teller) surface area and quite narrow pore size distribution. The ZrO2–CeO2 composition of as-prepared samples was confirmed by elemental X-ray microanalysis (EDS) and diffuse-reflectance UV/vis spectroscopy. The obtained Ce/ZrO2 nanocomposites demonstrated great application potential in oxidative catalysis. Catalysis studies showed that these new materials, which entail a high density of surface-active sites and open pore structure, are shown to be quite effective in the photo-oxidation of aryl alcohols. Our results indicated that the inclusion of CeO2 compounds in mesoporous structure has a beneficial effect on the catalytic activity of these materials. Although ZrO2 alone shows little photocatalytic activity, the Ce/ZrO2 heterostructures possess a remarkable activity and chemical stability for the photo-oxidation of various 1-phenyl and benzyl-alcohols to the corresponding ketones and aldehydes, under λ > 360 nm light irradiation, using molecular oxygen as oxidant.
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Language |
English, Greek |
Issue date |
2019-11-22 |
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/4/1/f/metadata-dlib-1574334815-206435-29371.tkl
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Views |
391 |