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5. Exploring metal carbamates as precursors for the synthesis of metal–organic frameworks.

Author

Volante, Stefania, Kloda, Matouš, Demel, Jan, Pampaloni, Guido, Marchetti, Fabio, Bresciani, Giulio, and Taddei, Marco

Subjects
NUCLEAR magnetic resonance spectroscopy, X-ray powder diffraction, COPPER, CRYSTALLIZATION kinetics, METAL chlorides
Abstract

In the synthesis of metal–organic frameworks (MOFs), the choice of the metal precursor plays a key role because of the influence that it can exert on the crystallization kinetics. The present work explores the use of metal-carbamato complexes for the synthesis of benchmark MOFs, namely HKUST-1 and UiO-66. Cu2(O2CNEt2)4·2NHEt2 and Zr(O2CNEt2)4, prepared using straightforward CO2 fixation reactions starting from the corresponding metal chlorides and diethylamine, were employed as metal precursors for MOF formation. The synthesis conditions, including the solvent, temperature, and ligand protonation degree, were systematically investigated, revealing metal carbamates as highly reactive precursors due to their prompt release of CO2 and amine upon reaction with protic species, i.e., the polycarboxylic linkers. This property of metal carbamates allowed us to identify room temperature protocols to achieve MOFs with comparable properties to those obtained using traditional metal precursors. Subsequent optimization of the reaction conditions led to the design of a one-pot synthetic strategy for HKUST-1, starting directly from copper(II) chloride and diethylamine under a CO2 atmosphere. The MOFs were characterized using various techniques, including powder X-ray diffraction, N2 sorption analysis, 1H nuclear magnetic resonance spectroscopy, and CHN elemental analysis, and compared to reference samples prepared according to literature procedures. [ABSTRACT FROM AUTHOR]

Published
2024
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6. “Activated Borane”: A Porous Borane Cluster Polymer as an Efficient Lewis Acid-Based Catalyst

Author

Lamač, Martin, primary, Urbán, Béla, additional, Horáček, Michal, additional, Bůžek, Daniel, additional, Leonová, Lucie, additional, Stýskalík, Aleš, additional, Vykydalová, Anna, additional, Škoch, Karel, additional, Kloda, Matouš, additional, Mahun, Andrii, additional, Kobera, Libor, additional, Lang, Kamil, additional, Londesborough, Michael G. S., additional, and Demel, Jan, additional

Published
2023
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14. Direct Phenylation of nido-B10H14

Author

Demel, Jan, primary, Kloda, Matouš, additional, Lang, Kamil, additional, Škoch, Karel, additional, Hynek, Jan, additional, Opravil, Adam, additional, Novotný, Matyáš, additional, Bould, Jonathan, additional, Ehn, Marcel, additional, and Londesborough, Michael G. S., additional

Published
2022
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15. Studium exfoliace vrstevnatých látek a jejich uplatnění v nanokompozitech

Author

Beneš, Ludvík (školitel), Čejka, Jiří, Demel, Jan, Tokarský, Jonáš, Kopecká, Kateřina, Beneš, Ludvík (školitel), Čejka, Jiří, Demel, Jan, Tokarský, Jonáš, and Kopecká, Kateřina

Abstract

Předkládaná práce se zabývá přípravou a charakterizací vrstevnatých materiálů ze skupiny fosfonátů a podvojných vrstevnatých hydroxidů. Tyto materiály jsou zkoumány z hlediska možnosti přípravy jejich nanoforem pomocí procesu exfoliace v kapalinách s následným uplatněním pro přípravu polymerních nanokompozitů. Významnou část práce tvoří studium procesu samotné exfoliace a vypracování metodiky pro reprodukovatelnou přípravu a hodnocení exfoliovaných materiálů. Dále jsou studovány způsoby dispergace připravených plniv do polymerních systémů, distribuce částic v polymerní matrici a vliv přítomnosti plniv na užitné vlastnosti nanokompozitu., The presented work deals with the preparation and characterization of layered materials from the group of phosphonates and double layered hydroxides. These materials are investigated in terms of the possibility of preparing their nanoform using the liquid-based exfoliation process. Theirsubsequent application for the preparation of polymer nanocompositesis evaluated. An important part of the work is the study of the process of exfoliation itself and the development of a methodology for reproducible preparation and evaluation of exfoliated materials. Furthermore, methods of dispersion of prepared fillers into polymer systems, distribution of particles in the polymer matrix and the influence of the presence of fillers on the utility properties of the nanocomposite are studied., Fakulta chemicko-technologická, Dokončená práce s úspěšnou obhajobou

Published
2022

16. Water-based synthesis and nitrate release properties of a ZrIV-based metal–organic framework derived from L-aspartic acid.

Author

Abodunrin, Temitope Olabisi, Kloda, Matou, Demel, Jan, and Taddei, Marco

Subjects
METAL-organic frameworks, NITRATES, ION exchange (Chemistry), AQUEOUS solutions, ELECTRODIALYSIS
Abstract

We report the synthesis and characterisation of a cationic metal–organic framework (MOF) based on ZrIV and L -aspartate and containing nitrate as an extra framework counteranion, named MIP-202-NO3. The ion exchange properties of MIP-202-NO3 were preliminarily investigated to evaluate its potential as a platform for controlled release of nitrate, finding that it readily releases nitrate in aqueous solution. [ABSTRACT FROM AUTHOR]

Published
2023
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20. “Activated Borane” – A Porous Borane Cluster Network

Author

Bůžek, Daniel, primary, Škoch, Karel, additional, Ondrušová, Soňa, additional, Kloda, Matouš, additional, Bavol, Dmytro, additional, Mahun, Andrii, additional, Kobera, Libor, additional, Lang, Kamil, additional, Londesborough, Michael G. S., additional, and Demel, Jan, additional

Published
2022
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28. Direct Phenylation of nido-B10H14.

Author

Demel, Jan, Kloda, Matouš, Lang, Kamil, Škoch, Karel, Hynek, Jan, Opravil, Adam, Novotný, Matyáš, Bould, Jonathan, Ehn, Marcel, and Londesborough, Michael G. S.

Published
2022
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37. Polymeric Membranes Containing Iodine-Loaded UiO-66 Nanoparticles as Water-Responsive Antibacterial and Antiviral Surfaces.

Author

Kirakci, Kaplan, Bůžek, Daniel, Peer, Petra, Liška, Vojtěch, Mosinger, Jiří, Křížová, Ivana, Kloda, Matouš, Ondrušová, Soňa, Lang, Kamil, and Demel, Jan

Abstract

The fight against pathogenic bacteria and viruses represents a challenging task requiring the development of innovative materials. The design of water-responsive disinfecting surfaces constitutes a pertinent endeavor to limit the spread of infectious pathogens that strive in wet environments and are often carried by the droplets or aerosols of biological fluids. In this context, we designed a polymeric nanostructured membrane which, when in contact with water, was able to release elemental iodine, a potent antimicrobial agent. The membrane was based on poly-(vinylidene fluoride-co-hexafluoropropylene) electrospun nanofibers containing nanoparticles of an archetypal metal–organic framework (MOF), UiO-66. The gas adsorption capacity of the MOF container was preserved upon incorporation into the polymeric nanofibers, which also exerted a protective effect against the fast structural collapse of UiO-66 in phosphate-buffered saline, a model for biological fluids. The membrane loaded high amounts of iodine via gas diffusion and its release was (mostly) triggered by contact with the aqueous medium. The antibacterial activity of the membrane was tested against the Escherichia coli strain DH5α and revealed prompt and robust disinfecting properties. The membrane also efficiently inhibited the infectivity of viral model vesicular stomatitis virus glycoprotein pseudotyped HIV-1 particles in HEK-293 cells in a short time. The observed synergistic effects between the MOF container and the polymeric support material constitute attractive features for the development of MOF-based materials for biological applications. [ABSTRACT FROM AUTHOR]

Published
2022
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38. New directions in metal phosphonate and fhosphinate chemistry

Author

Shearan, Stephen J.I., Stock, Norbert, Emmerling, Franziska, Demel, Jan, Wright, Paul A., Demadis, Konstantinos D., Vassaki, Maria, Costantino, Ferdinando, Vivani, Riccardo, Sallard, Sébastien, Salcedo, Inés R., Cabeza-Diaz, Aurelio, and Taddei, Marco

Subjects
Fosfatos, Metal–organic frameworks, Baterías de estado sólido, Gas sorption/separation, Pilas de combustible, Rechargeable batteries, Hterogeneous catalysis, Synthesis, Metal phosphonates and phosphinate, X-ray and electron diffraction, Drug delivery, Layered materials, Conductividad eléctrica, In situ characterisation, Fósforo - Compuestos, Proton conduction
Abstract

In September 2018, the First EuropeanWorkshop on Metal Phosphonates Chemistry brought together some prominent researchers in the field of metal phosphonates and phosphinates with the aim of discussing past and current research e orts and identifying future directions. The scope of this perspective article is to provide a critical overview of the topics discussed during the workshop, which are divided into two main areas: synthesis and characterisation, and applications. In terms of synthetic methods, there has been a push towards cleaner and more e cient approaches. This has led to the introduction of high-throughput synthesis and mechanochemical synthesis. The recent success of metal–organic frameworks has also promoted renewed interest in the synthesis of porous metal phosphonates and phosphinates. Regarding characterisation, the main advances are the development of electron di raction as a tool for crystal structure determination and the deployment of in situ characterisation techniques, which have allowed for a better understanding of reaction pathways. In terms of applications, metal phosphonates have been found to be suitable materials for several purposes: they have been employed as heterogeneous catalysts for the synthesis of fine chemicals, as solid sorbents for gas separation, notably CO2 capture, as materials for electrochemical devices, such as fuel cells and rechargeable batteries, and as matrices for drug delivery.

Published
2019

41. New Directions in Metal Phosphonate and Phosphinate Chemistry

Author

Shearan, Stephen J.I., primary, Stock, Norbert, additional, Emmerling, Franziska, additional, Demel, Jan, additional, Wright, Paul A., additional, Demadis, Konstantinos D., additional, Vassaki, Maria, additional, Costantino, Ferdinando, additional, Vivani, Riccardo, additional, Sallard, Sébastien, additional, Ruiz Salcedo, Inés, additional, Cabeza, Aurelio, additional, and Taddei, Marco, additional

Published
2019
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