H₅PV₂Mo₁₀O₄₀ Polyoxometalate Encapsulated in NU-1000 Metal–Organic Framework for Aerobic Oxidation of a Mustard Gas Simulant

The immobilization of H5PV2Mo10O40 polyoxometalates (POMs) in the in the mesoporous channel-type metal–organic framework (MOF), NU-1000, via simple impregnation method is reported here. Characterization of the composite PV2Mo10@NU-1000 activated by supercritical CO2 revealed that the POMs occupy the mesopore. Upon heating as low as 40 °C in the absence of bulk solvent, the POMs migrate to the micropore. However, the presence of solvent, such as cyclohexane, impedes this transformation. The material was active for the aerobic oxidation of the mustard gas simulant, 2-chloroethyl ethyl sulfide (CEES), in cyclohexane using isobutyraldehyde a sacrificial reductant and O2 as the oxidant. The activity of the POM allowed for efficient oxidation of CEES in the dark and in air. Immobilization of the POM in the MOF was found to improve the initial turnover frequency compared to the POM itself. Further, the POM catalyst was found to be unstable under the chosen reaction conditions and no activity was found upon washing and reusing the POM. As a composite PV2Mo10@NU-1000, the POMs retained their catalytic activity and allowed for recycling of the catalytic material

Reticular Access to Highly Porous <b>acs</b>-MOFs with Rigid Trigonal Prismatic Linkers for Water Sorption

Metal–organic frameworks (MOFs) based on edge-transitive 6-c acs nets are well-developed and can be synthesized from trinuclear metal clusters and ditopic ligands, i.e., MOF-235 and MIL-88. The rational design of noncatenated acs-MOFs by symmetry-matching between trigonal prismatic organic ligands and trinuclear clusters, however, remains a great challenge. Herein, we report a series of acs-MOFs (NU-1500) based on trivalent trinuclear metal (Fe3+, Cr3+, and Sc3+) clusters and a rigid trigonal prismatic ligand courtesy of reticular chemistry. The highly porous and hydrolytically stable NU-1500-Cr can be activated directly from water and displays an impressive water vapor uptake with small hysteresis

Reticular Access to Highly Porous <b>acs</b>-MOFs with Rigid Trigonal Prismatic Linkers for Water Sorption

Metal–organic frameworks (MOFs) based on edge-transitive 6-c acs nets are well-developed and can be synthesized from trinuclear metal clusters and ditopic ligands, i.e., MOF-235 and MIL-88. The rational design of noncatenated acs-MOFs by symmetry-matching between trigonal prismatic organic ligands and trinuclear clusters, however, remains a great challenge. Herein, we report a series of acs-MOFs (NU-1500) based on trivalent trinuclear metal (Fe3+, Cr3+, and Sc3+) clusters and a rigid trigonal prismatic ligand courtesy of reticular chemistry. The highly porous and hydrolytically stable NU-1500-Cr can be activated directly from water and displays an impressive water vapor uptake with small hysteresis

Reticular Access to Highly Porous <b>acs</b>-MOFs with Rigid Trigonal Prismatic Linkers for Water Sorption

Metal–organic frameworks (MOFs) based on edge-transitive 6-c acs nets are well-developed and can be synthesized from trinuclear metal clusters and ditopic ligands, i.e., MOF-235 and MIL-88. The rational design of noncatenated acs-MOFs by symmetry-matching between trigonal prismatic organic ligands and trinuclear clusters, however, remains a great challenge. Herein, we report a series of acs-MOFs (NU-1500) based on trivalent trinuclear metal (Fe3+, Cr3+, and Sc3+) clusters and a rigid trigonal prismatic ligand courtesy of reticular chemistry. The highly porous and hydrolytically stable NU-1500-Cr can be activated directly from water and displays an impressive water vapor uptake with small hysteresis

Regulation of Catenation in Metal–Organic Frameworks with Tunable Clathrochelate-Based Building Blocks

Inherent pore structures and pore environment of metal–organic frameworks (MOFs) have a significant impact on the macroscopic functionalities. In this regard, it is valuable to explore the regulation of catenation and then tune the pore structures and pore environment, optimally at the molecular level. Here we report regulating the catenation of Zn-MOFs based on the primitive cubic (pcu) net, isoreticular to MOF-5, via fine-tuning the clathrochelate-based ditopic building blocks. The use of clathrochelate-based carboxylate ligands with bulky cores of n-butyl groups led to the synthesis of a Zn-MOF with the pcu net, while clathrochelate linkers with relatively fewer bulky cores give a twofold interpenetrated Zn-MOF structure under similar conditions

Reticular Access to Highly Porous <b>acs</b>-MOFs with Rigid Trigonal Prismatic Linkers for Water Sorption

Metal–organic frameworks (MOFs) based on edge-transitive 6-c acs nets are well-developed and can be synthesized from trinuclear metal clusters and ditopic ligands, i.e., MOF-235 and MIL-88. The rational design of noncatenated acs-MOFs by symmetry-matching between trigonal prismatic organic ligands and trinuclear clusters, however, remains a great challenge. Herein, we report a series of acs-MOFs (NU-1500) based on trivalent trinuclear metal (Fe3+, Cr3+, and Sc3+) clusters and a rigid trigonal prismatic ligand courtesy of reticular chemistry. The highly porous and hydrolytically stable NU-1500-Cr can be activated directly from water and displays an impressive water vapor uptake with small hysteresis

Hot Press Synthesis of MOF/Textile Composites for Nerve Agent Detoxification

Chemical nerve agents employed in warfare can induce paralysis and death within minutes of exposure. Zirconium-based metal–organic frameworks (MOFs), such as UiO-66-NH2, show promise for the fast and efficient decontamination of nerve agents, which motivates their incorporation into textiles as protective layers. Few scalable methods to produce MOF/textile composites for personal protective applications have been developed; however, they mainly require the use of toxic and flammable solvents. Here, we describe a scalable, single-step method to synthesize UiO-66-NH2 on cotton fabrics by hot pressing the monomers onto the fabric samples. The use of a preformed hexanuclear zirconium benzoate cluster with 1,8-bis­(dimethylamine)­naphthalene as a non-nucleophilic base improved the quality of MOFs synthesized from the hot press method, as determined by an increase in their surface area and crystallinity. Preactivation of the cotton fabric with carboxylic acids provided UiO-66-NH2/cotton composites of high MOF loadings with homogeneous coverage, which demonstrated efficient decontamination of a nerve agent simulant, dimethyl-4-nitrophenyl phosphate (DMNP)

Phase Transitions in Metal–Organic Frameworks Directly Monitored through In Situ Variable Temperature Liquid-Cell Transmission Electron Microscopy and In Situ X‑ray Diffraction

Zr6-based metal–organic frameworks (MOFs) with tetratopic organic linkers have been extensively investigated owing to their versatile structural tunability. While diverse topologies and polymorphism in the resulting MOFs are often encountered with tetratopic linkers and Zr6 nodes, reports on phase transitions within these systems are rare. Thus, we have a limited understanding of polymorph transformations, hindering the rational development of pure phase materials. In this study, a phase transition from a microporous MOF, scu-NU-906, to a mesoporous MOF, csq-NU-1008, was discovered and monitored through in situ variable temperature liquid-cell transmission electron microscopy (VT-LCTEM), high-resolution transmission electron microscopy (HRTEM), and in situ variable temperature powder X-ray diffraction (VT-PXRD). It was found that the microporous- to-mesoporous transformation in the presence of formic acid occurs via a concomitant dissolution–reprecipitation process

Hot Press Synthesis of MOF/Textile Composites for Nerve Agent Detoxification

Chemical nerve agents employed in warfare can induce paralysis and death within minutes of exposure. Zirconium-based metal–organic frameworks (MOFs), such as UiO-66-NH2, show promise for the fast and efficient decontamination of nerve agents, which motivates their incorporation into textiles as protective layers. Few scalable methods to produce MOF/textile composites for personal protective applications have been developed; however, they mainly require the use of toxic and flammable solvents. Here, we describe a scalable, single-step method to synthesize UiO-66-NH2 on cotton fabrics by hot pressing the monomers onto the fabric samples. The use of a preformed hexanuclear zirconium benzoate cluster with 1,8-bis­(dimethylamine)­naphthalene as a non-nucleophilic base improved the quality of MOFs synthesized from the hot press method, as determined by an increase in their surface area and crystallinity. Preactivation of the cotton fabric with carboxylic acids provided UiO-66-NH2/cotton composites of high MOF loadings with homogeneous coverage, which demonstrated efficient decontamination of a nerve agent simulant, dimethyl-4-nitrophenyl phosphate (DMNP)