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arXiv · 1510.08220

Connecting Defects and Amorphization in UiO-66 and MIL-140 Metal-organic Frameworks: A Combined Experimental and Computational Study

Thomas D. Bennett·Tanya K. Todorova·Emma F. Baxter·David. G. Reid·Christel Gervais·Bart Bueken·B. Van de Voorde·Dirk De Vos·David A. Keen·Caroline Mellot-Draznieks
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Abstract

The mechanism and products of the structural collapse of the metal-organic frameworks (MOFs) UiO-66, MIL-140B and MIL-140C upon ball-milling are investigated through solid state 13C NMR and pair distribution function (PDF) studies, finding amorphization to proceed by the breaking of a fraction of metal-ligand bonding in each case. The amorphous products contain inorganic-organic bonding motifs reminiscent of the crystalline phases. Whilst the inorganic Zr6O4(OH)4 clusters of UiO-66 remain intact upon structural collapse, the ZrO backbone of the MIL-140 frameworks undergoes substantial distortion. Density functional theory calculations have been performed to investigate defective models of MIL-140B and show, through comparison of calculated and experimental 13C NMR spectra, that amorphization and defects in the materials are linked.

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Thomas D. Bennett, Tanya K. Todorova, Emma F. Baxter, David. G. Reid, Christel Gervais, Bart Bueken, B. Van de Voorde, Dirk De Vos, David A. Keen, Caroline Mellot-Draznieks. 2015-10-28. Connecting Defects and Amorphization in UiO-66 and MIL-140 Metal-organic Frameworks: A Combined Experimental and Computational Study. https://doi.org/10.1039/c5cp06798g

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