Single-crystal electron diffraction has shown to be powerful for structure determination of nano- and submicron-sized crystals that are too small to be studied by single-crystal X-ray diffraction. However, it has been very challenging to obtain high quality electron diffraction data from beam sensitive crystals such as metal-organic frameworks (MOFs). It is even more difficult to locate guest species in the pores of MOF crystals.
View Article and Find Full Text PDFThe Ni-metallated porphyrin-based tetraphosphonic acid (Ni-tetra(4-phosphonophenyl)porphyrin, Ni-HTPPP) was used for the synthesis of highly porous metal phosphonates containing the tetravalent cations Zr and Hf. The compounds were thoroughly characterized regarding their sorption properties towards N and HO as well as thermal and chemical stability. During the synthesis optimization the reaction time could be substantially decreased under stirring from 24 to 3 h in glass vials.
View Article and Find Full Text PDFThe new porphyrin-based tetraphosphonic acid (Ni-HTPPP) was employed in the synthesis of four isostructural MOFs of composition [M(Ni-HTPPP)(HO)], denoted CAU-29 (M = Mn, Co, Ni, Cd). Ni-CAU-29 was thoroughly characterized regarding its thermal and chemical stability as well as for proton conductivity.
View Article and Find Full Text PDFA precursor method has been developed to synthesize Ce(iv) MOFs that could not be prepared directly from Ce(iv) salts. Starting from Ce clusters, two Ce-UiO-66 analogues and four tetracarboxylate-based Ce(iv) MOFs could be synthesized. The applied method facilitates framework formation by evading reactive individual Ce(iv)-ions thereby paving the way for further development of Ce-MOFs.
View Article and Find Full Text PDFTwo porphyrin-based metal-organic frameworks (MOFs) containing gallium or indium, [Ga2(OH)2(H2TCPP)]·3DMF·3H2O (Ga-PMOF) and [In2(OH)2(H2TCPP)]·3DMF·4H2O (In-PMOF) (H6TCPP = 4-tetracarboxyphenylporphyrin), were discovered using high-throughput methods. The structure was refined by the Rietveld-method starting from the structure model of Al-PMOF, [Al2(OH)2(H2TCPP)]. The new PMOFs exhibit BET surface areas between 1150 and 1400 m(2) g(-1) and are also porous toward CO2 (Ga-PMOF, 15.
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