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Exploratory research into the critical steps in metal-organic framework (MOF) activation involving solvent exchange and solvent evacuation are reported. It is discovered that solvent exchange kinetics are extremely fast, and minutes rather days are appropriate for solvent exchange in many MOFs. It is also demonstrated that choice of a very low surface tension solvent is critical in successfully activating challenging MOFs. MOFs that have failed to be activated previously can achieve predicted surface areas provided that lower surface tension solvents, such as n-hexane and perfluoropentane, are applied. The insights herein aid in the efficient activation of MOFs in both laboratory and industrial settings and provide best practices for avoiding structural collapse. [ABSTRACT FROM AUTHOR]

The design, synthesis, and properties of the new microporous coordination polymer UMCM-310 are described. The unique electronic character of the perylene-based linker enables selective interaction with electron-poor aromatics leading to efficient separation of nitroaromatics. UMCM-310 possesses high surface area and large pore size and thus permits the separation of large organic molecules based on adsorption rather than size exclusion. [ABSTRACT FROM AUTHOR]

Design and synthesis of porous solids employing both reversible coordination chemistry and reversible covalent bond formation is described. The combination of two different linkage modes in a single material presents a link between two distinct classes of porous materials as exemplified by metal-organic frameworks (MOFs) and covalent organic frameworks (COFs). This strategy, in addition to being a compelling material-discovery method, also offers a platform for developing a fundamental understanding of the factors influencing the competing modes of assembly. We also demonstrate that even temporary formation of reversible connections between components may be leveraged to make new phases thus offering design routes to polymorphic frameworks. Moreover, this approach has the striking potential of providing a rich landscape of structurally complex materials from commercially available or readily accessible feedstocks. [ABSTRACT FROM AUTHOR]

Because of their high surface areas,crystallinity, and tunableproperties, metal–organic frameworks (MOFs) have attractedintense interest as next-generation materials for gas capture andstorage. While much effort has been devoted to the discovery of newMOFs, a vast catalog of existing MOFs resides within the CambridgeStructural Database (CSD), many of whose gas uptake properties havenot been assessed. Here we employ data mining and automated structureanalysis to identify, “cleanup,” and rapidly predictthe hydrogen storage properties of these compounds. Approximately20 000 candidate compounds were generated from the CSD usingan algorithm that removes solvent/guest molecules. These compoundswere then characterized with respect to their surface area and porosity.Employing the empirical relationship between excess H2uptakeand surface area, we predict the theoretical total hydrogen storagecapacity for the subset of ∼4000 compounds exhibiting nontrivialinternal porosity. Our screening identifies several overlooked compoundshaving high theoretical capacities; these compounds are suggestedas targets of opportunity for additional experimental characterization.More importantly, screening reveals that the relationship betweengravimetric and volumetric H2density is concave downward,with maximal volumetric performance occurring for surface areas of3100–4800 m2/g. We conclude that H2storagein MOFs will not benefit from further improvements in surface areaalone. Rather, discovery efforts should aim to achieve moderate massdensities and surface areas simultaneously, while ensuring frameworkstability upon solvent removal. [ABSTRACT FROM AUTHOR]

This paper describes the heterogenization of single-site transition-metal catalysts in metal–organic frameworks (MOFs) via cation exchange. A variety of cationic complexes of Pd, Fe, Ir, Rh, and Ru have been incorporated into ZJU-28, and the new materials have been characterized by optical microscopy, inductively coupled plasma optical emission spectroscopy, and powder X-ray diffraction. MOF-supported [Rh(dppe)(COD)]BF4 catalyzes the hydrogenation of 1-octene to n-octane. The activity of this supported catalyst compares favorably to its homogeneous counterpart, and it can be recycled at least four times. Overall, this work provides a new and general approach for supporting transition-metal catalysts in MOFs. [ABSTRACT FROM AUTHOR]