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Herein, we present an integrated upper division chemistry laboratory experiment involving the synthesis, characterization, and evaluation of catalytic metal–organic frameworks (MOFs). Experiments are designed to facilitate the solvothermal synthesis and characterize MOFs, including UiO-66, UiO-66-NH2, and UiO-66-NO2. The MOFs are employed as catalysts in oxidative desulfurization (ODS) of an organic sulfur-containing compound, dibenzothiophene (DBT), in a laboratory experiment. To investigate the composition and structure of the MOFs, powder X-ray diffraction (PXRD) and elemental analysis (EA), respectively, are employed. Using Fourier transform infrared (FT-IR) spectroscopy, students evaluate the different organic linkers found in the MOFs. Students then investigate the effects of the electronic environment of the organic linker of the MOFs on the ODS of DBT. Students find that all three porous and crystalline MOFs oxidize DBT, but UiO-66-NO2 exhibits the most efficient catalytic conversion.
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Ionothermal Synthesis of Metal‐Organic Frameworks Using Low‐Melting Metal Salt Precursors**
Abstract Metal‐organic frameworks (MOFs) are porous, crystalline materials constructed from organic linkers and inorganic nodes with myriad potential applications in chemical separations, catalysis, and drug delivery. A major barrier to the application of MOFs is their poor scalability, as most frameworks are prepared under highly dilute solvothermal conditions using toxic organic solvents. Herein, we demonstrate that combining a range of linkers with low‐melting metal halide (hydrate) salts leads directly to high‐quality MOFs without added solvent. Frameworks prepared under these ionothermal conditions possess porosities comparable to those prepared under traditional solvothermal conditions. In addition, we report the ionothermal syntheses of two frameworks that cannot be prepared directly under solvothermal conditions. Overall, the user‐friendly method reported herein should be broadly applicable to the discovery and synthesis of stable metal‐organic materials.
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- Award ID(s):
- 1719875
- PAR ID:
- 10401989
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 62
- Issue:
- 17
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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