Stephen Fordham

Topology-Guided Design and Syntheses of Highly Stable Mesoporous Porphyrinic Zirconium Metal–Organic Frameworks with High Surface Area

Through a topology-guided strategy, a series of Zr6-containing isoreticular porphyrinic metal-organic frameworks (MOFs), PCN-228, PCN-229, and PCN-230, with ftw-a topology were synthesized using the extended porphyrinic linkers. The bulky porphyrin ring ligand effectively prevents the network interpenetration which often appears in MOFs with increased linker length. The pore apertures of the structures range from 2.5 to 3.8 nm, and PCN-229 demonstrates the highest porosity and BET surface area among the previously reported Zr-MOFs. Additionally, by changing the relative direction of the terminal phenyl rings, this series replaces a Zr8 cluster with a smaller Zr6 cluster in a topologically identical framework. The high connectivity of the Zr6 cluster yields frameworks with enhanced stability despite high porosity and ultralarge linker. As a representative example, PCN-230, constructed with the most extended porphyrinic linker, shows excellent stability in aqueous solutions with pH values ranging from 0 to 12 and demonstrates one of the highest pH tolerances among all porphyrinic MOFs. This work not only presents a successful example of rational design of MOFs with desired topology, but also provides a strategy for construction of stable mesoporous MOFs.

Kinetically tuned dimensional augmentation as a versatile synthetic route towards robust metal-organic frameworks.

Metal-organic frameworks with high stability have been pursued for many years due to the sustainability requirement for practical applications. However, researchers have had great difficulty synthesizing chemically ultra-stable, highly porous metal-organic frameworks in the form of crystalline solids, especially as single crystals. Here we present a kinetically tuned dimensional augmentation synthetic route for the preparation of highly crystalline and extremely robust metal-organic frameworks with a preserved metal cluster core. Through this versatile synthetic route, we obtain large single crystals of 34 different iron-containing metal-organic frameworks. Among them, PCN-250(Fe2Co) exhibits high volumetric uptake of hydrogen and methane, and is also stable in water and aqueous solutions with a wide range of pH values.

Stepwise Synthesis of Robust Metal–Organic Frameworks via Postsynthetic Metathesis and Oxidation of Metal Nodes in a Single-Crystal to Single-Crystal Transformation

Utilizing PCN-426-Mg as a template, two robust metal-organic frameworks (MOFs), PCN-426-Fe(III) and PCN-426-Cr(III), have been synthesized through a strategy of postsynthetic metathesis and oxidation (PSMO) of the metal nodes step by step. The frameworks remained in their single crystal form throughout. Furthermore, the stability and porosity of the frameworks were significantly improved after PSMO. By taking advantage of both the kinetically labile metal-ligand exchange reactions prior to oxidation and the kinetically inert metal-ligand bonds after oxidation, robust MOFs, which would otherwise be difficult to synthesize, can be readily prepared.

Lanthanide Metal-Organic Frameworks: Syntheses, Properties, and Potential Applications

Metal-organic frameworks (MOFs) have emerged as a novel category of porous materials. Currently, rational design of MOFs provides a convenient method to design MOFs with desired properties. After a short introduction of traditional metal MOFs, this chapter discusses the development, properties, and applications of Lanthanide MOFs (Ln-MOFs). Ln-MOFs have garnered much interest due to a wide array of features from the marriage of lanthanide ions with traditional MOFs. An introduction to the Ln-MOF field is presented with several well-known structures to demonstrate various synthetic strategies. Furthermore, interesting structural and chemical properties including porosity, chirality, magnetism, and luminescence are highlighted from recent studies, as well as, a brief overview of potential applications including gas storage, catalysis, and chemical sensing.

Crystal engineering on superpolyhedral building blocks in metal-organic frameworks applied in gas adsorption.

Two metal-organic frameworks [PCN-426(Ni) and PCN-427(Cu)] have been designed and synthesized to investigate the structure predictability using a SBB (supermolecular building blocks) approach. Tetratopic ligands featuring 120° angular carboxylate moieties were coordinated with a [Ni3(μ3-O)] cluster and a [Cu2O2] unit, respectively. As topologically predicted, 4-connected networks with square coordination adopted the nbo net for the Ni-MOF and ssb net for the Cu-MOF. PCN-426(Ni) was augmented with 12-connected octahedral SBBs, while PCN-427(Cu) was constructed with tetragonal open channels. After a CO2 supercritical drying procedure, the PCN-426(Ni) possessed a Brunauer-Emmett-Teller (BET) surface area as high as 3935 m(2) g(-1) and impressively high N2 uptake of 1500 cm(3) g(-1). This work demonstrates the generalization of the SBB strategy, finding an alternative to inconvenient synthetic processes to achieve the desired structural features.

Erratum: Corrigendum: Kinetically tuned dimensional augmentation as a versatile synthetic route towards robust metal–organic frameworks

Nature Communications 5: Article number: 5723 (2014); Published: 4 December 2014; Updated: 5 February 2015 The financial support for this Article was not fully acknowledged. The Acknowledgements should have read: This work was supported as part of the Methane Opportunities for Vehicular Energy (MOVE) Program under the Award Number DE-AR0000249 and as part of the Center for Gas Separations Relevant to Clean Energy Technologies, an Energy Frontier Research Center (EFRC) funded by the U.

CCDC 975820: Experimental Crystal Structure Determination

Related Article: Dawei Feng, Kecheng Wang, Zhangwen Wei, Ying-Pin Chen, Cory M. Simon, Ravi Arvapally, Richard L. Martin, Mathieu Bosch, Tian-Fu Liu, Stephen Fordham, Daqiang Yuan, Mohammad A. Omary, Maciej Haranczyk, Berend Smit, Hong-Cai Zhou|2014|Nat.Commun.|5|5723|doi:10.1038/ncomms6723