TY - CONF A1 - Heinekamp, Christian A1 - Kneiske, Sönke A1 - Guiherme Buzanich, Ana A1 - Ahrens, Mike A1 - Braun, Thomas A1 - Emmerling, Franziska T1 - A fluorolytic sol-gel route to access an amorphous Lewis-acidic Zr fluoride catalyst N2 - The Kemnitz et al. developed a fluorolytic route to access metal fluorides 1 such as AlF3 2 and MgF2 3 which possess a high surface area. In aluminium-based systems, the synthetic approach led to amorphous xerogels that can be further converted into Lewis superacids.2 Still, despite zirconium oxide being described as a stronger Lewis acid than other metal oxides4 zirconium fluoride-based materials have only recently been reported or investigated. In this work we extend the class of amorphous Lewis acidic heterogeneous catalysts to an amorphous ZrF4 that is active in C-F bond activation. T2 - CRC 1349 Summer School 2023 CY - Berlin, Germany DA - 28.08.2023 KW - ZrF4 KW - Heterogeneous catalysis KW - C-F bond activation KW - Postfluorination PY - 2023 AN - OPUS4-58638 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heinekamp, Christian A1 - Kneiske, Sönke A1 - Guilherme Buzanich, Ana A1 - Ahrens, Mike A1 - Braun, Thomas A1 - Emmerling, Franziska T1 - A fluorolytic sol-gel route to access an amorphous Zr fluoride catalyst: A useful tool for C-F bond activation JF - Catalysis Science & Technology N2 - A route to a ZrF4 catalyst active in room temperature Friedel–Crafts and dehydrofluorination reactions was developed via a fluorolytic sol–gel route, which was followed by a postfluorination step using a stream of CHClF2. The behaviour of different Zr(IV) precursors in a sol–gel reaction with anhydrous isopropanol/HF solution was investigated. The subsequent post-fluorination step was optimised in its temperature ramp and confirmed the necessity of a fluorination of the generated xerogels to obtain catalytic activity. The process is discussed in the context of the analysis of the materials using Brunauer–Emmett–Teller analysis (BET), powder X-ray diffraction (XRD), infrared spectroscopy (IR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The local structure of the amorphous catalyst was elucidated by extended X-ray absorption fine structure spectroscopy (EXAFS). KW - Catalysis KW - Heterogeneous catalysis KW - C-F bond activation KW - Postfluorination PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593433 DO - https://doi.org/10.1039/D3CY01439H SN - 2044-4761 SP - 1 EP - 8 PB - Royal Society of Chemistry (RSC) AN - OPUS4-59343 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -