Modulating active sites in MOFs for improved Lewis acid or base catalysis

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Modeling Lewis catalyzed reactions in Metal Organic Frameworks

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Modeling citronellal cyclization in Cu3BTC2 and UiO-66

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A breathing zirconium metal-organic framework with reversible loss of crystallinity by correlated nanodomain formation

The isoreticular analogue of the metal-organic framework UiO-66(Zr), synthesized with the flexible trans-1,4-cyclohexanedicarboxylic acid as linker, shows a peculiar breathing behavior by reversibly losing long-range crystalline order upon evacuation. The underlying flexibility is attributed to a concerted conformational contraction of up to two thirds of the linkers, which breaks the local lattice symmetry. X-ray scattering data are described well by a nanodomain model in which differently oriented tetragonal-type distortions propagate over about 7-10 unit cells

Improving the mechanical stability of zirconium-based metal-organic frameworks by incorporation of acidic modulators

Acidic modulating ligands have been shown to stabilize UiO metal-organic frameworks against structural collapse under ball-milling.T.D.B. would like to thank Trinity Hall for funding, along with Professor Anthony K. Cheetham for use of lab facilities. D.D.V. is grateful to IWT (MOF Shape), KU Leuven for support in the Metusalem grant CASAS and IAP 7/05 Functional Supramolecular Systems. I.S. and B.B. thank Research Foundation – Flanders (FWO) for Ph.D. fellowships.This is the accepted manuscript. The final published version is available from RSC at http://pubs.rsc.org/en/Content/ArticleLanding/2015/TA/c4ta06396a#!divAbstract

The impact of post-synthetic linker functionalization of MOFs on methane storage: The role of defects

Natural gas is increasingly being viewed as one of the most viable alternatives to gasoline. However, its vehicular application will only be widespread if safe and high-capacity methane stores are developed. In this work, we report an over 33% increase in methane uptake on a post-synthetically modified metal–organic framework. The underlying mechanism for this dramatic increase is due to lattice defects formed upon post-synthetic modification. This method may open new approaches to natural gas storage

Shape Selectivity by Guest- Driven Restructuring of a Porous Material

A flexible metal-organic framework selectively sorbs para- (pX) over meta-xylene (mX) by synergic restructuring around pX coupled with generation of unused void space upon mX loading. The nature of the structural change suggests more generally that flexible structures which are initially mismatched in terms of fit and capacity to the preferred guest are strong candidates for effective molecular separations