The object of this thesis is to get a deeper understanding of the role of modulator agents in the synthesis of Zr- and Hf-based metal-organic frameworks (MOFs) and their impact on framework properties, such as textural properties, stability, hydrophobicity, and catalytic activity. For this purpose, MOFs are investigated that are built up by the commercially available linker 2,5-thiophenedicarboxylate and the Zr6(µ3-O)4(µ3-OH)412+ cluster. With proper choice of the modulator a new structure, namely DUT-126 (DUT = Dresden University of Technology), could be presented in the course of this work, besides the already known polymorphs of DUT-67, DUT-68 and DUT-69.
Furthermore, DUT-67 is chosen as a model structure to functionalise the metal cluster of the framework by exchanging the modulator post-synthetically with hydrophobic fluorinated monocarboxylic acids. With the introduction of these fluorinated molecules, the surface polarities and the stability against water removal can be tuned. In addition, the metal clusters of DUT-67 were modified with a complete removal of the pristine modulator molecules by means of an acidic treatment in order to generate open metal sites that can function as Lewis acid sites. The suitability of DUT-67 and its acid treated analogues as heterogenous catalyst was tested on the Meerwein-Ponndorf-Verley reduction of cyclohexanone.
Furthermore, the UiO-67 analogue DUT-122, which contains the luminescent linker 9-fluorenone-2,7-dicarboxylate, was tested as sensor material to detect solvent vapours. It could be shown that DUT-122 is sensitive to various solvent vapours, which induce photoluminescent shifts and intensity changes of the fluorescence emission profile depending on the polarity and the functionality of the respective solvent.
Identifer | oai:union.ndltd.org:DRESDEN/oai:qucosa.de:bsz:14-qucosa-235346 |
Date | 12 June 2018 |
Creators | Drache, Franziska |
Contributors | Technische Universität Dresden, Fakultät Mathematik und Naturwissenschaften, Prof. Dr. rer. nat. habil. Stefan Kaskel, Prof. Dr. rer. nat. habil. Stefan Kaskel, Prof. Dr. rer. nat. habil. Eike Brunner |
Publisher | Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden |
Source Sets | Hochschulschriftenserver (HSSS) der SLUB Dresden |
Language | English |
Detected Language | English |
Type | doc-type:doctoralThesis |
Format | application/pdf |
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