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The indoor air quality is of prime importance for human daily life and health, for which the adsorbents like zeolites and silica‐gels are widely used for air dehumidification and harmful gases capture. Herein, we develop a pore‐nanospace post‐engineering strategy to optimize the hydrophilicity, water‐uptake capacity and air‐purifying ability of metal‐organic frameworks (MOFs) with long‐term stability, offering an ideal candidate with autonomous multi‐functionality of moisture control and pollutants sequestration. Through variant tuning of organic‐linkers carrying hydrophobic and hydrophilic groups in the pore‐nanospaces of prototypical UiO‐67, a moderately hydrophilic MOF (UiO‐67‐4Me‐NH2‐38 %) with high thermal, hydrolytic and acid‐base stability is screened out, featuring S‐shaped water sorption isotherms exactly located in the recommended comfortable and healthy ranges of relative humidity for indoor ventilation (45 %–65 % RH) and adverse health effects minimization (40–60 % RH). Its exceptional attributes of water‐uptake working capacity/efficiency, contaminants removal, recyclability and regeneration promise a great potential in confined indoor environment application. [ABSTRACT FROM AUTHOR]

The indoor air quality is of prime importance for human daily life and health, for which the adsorbents like zeolites and silica‐gels are widely used for air dehumidification and harmful gases capture. Herein, we develop a pore‐nanospace post‐engineering strategy to optimize the hydrophilicity, water‐uptake capacity and air‐purifying ability of metal‐organic frameworks (MOFs) with long‐term stability, offering an ideal candidate with autonomous multi‐functionality of moisture control and pollutants sequestration. Through variant tuning of organic‐linkers carrying hydrophobic and hydrophilic groups in the pore‐nanospaces of prototypical UiO‐67, a moderately hydrophilic MOF (UiO‐67‐4Me‐NH2‐38 %) with high thermal, hydrolytic and acid‐base stability is screened out, featuring S‐shaped water sorption isotherms exactly located in the recommended comfortable and healthy ranges of relative humidity for indoor ventilation (45 %–65 % RH) and adverse health effects minimization (40–60 % RH). Its exceptional attributes of water‐uptake working capacity/efficiency, contaminants removal, recyclability and regeneration promise a great potential in confined indoor environment application. [ABSTRACT FROM AUTHOR]

We transformed the hydrophilic metal–organic framework (MOF) UiO‐67 into hydrophobic UiO‐67‐Rs (R=alkyl) by introducing alkyl chains into organic linkers, which not only protected hydrophilic Zr6O8 clusters to make the MOF interspace superoleophilic, but also led to a rough crystal surface beneficial for superhydrophobicity. The UiO‐67‐Rs displayed high acid, base, and water stability, and long alkyl chains offered better hydrophobicity. Good hydrophobicity/oleophilicity were also possible with mixed‐ligand MOFs containing metal‐binding ligands. Thus, a (super)hydrophobic MOF catalyst loaded with Pd centers efficiently catalyzed Sonogashira reactions in water at ambient temperature. Studies of the hydrophobic effects of the coordination interspace and the outer surface suggest a simple de novo strategy for the synthesis of superhydrophobic MOFs that combine surface roughness and low surface energy. Such MOFs have potential for environmentally friendly catalysis and water purification. [ABSTRACT FROM AUTHOR]

We report a convenient approach, the first of its kind, to construct a microscale non-metal@MOF composite catalytic host–guest system for an organic tandem reaction. The reported porous Cu4I4-MOF is able to reversibly adsorb molecular iodine at room temperature. The obtained I2@Cu4I4-MOF host–guest system can be a highly heterogeneous catalyst to promote the Friedel–Crafts alkylation of indoles with acetals in a one-pot two-step fashion under solvent-free conditions at room temperature. [ABSTRACT FROM AUTHOR]

The design and creation of soft porous crystals combining regularity and flexibility may promote potential applications for gas storage and separation due to their deformable framework's responsiveness to external stimuli. The flexibility of metal–organic frameworks (MOFs) relies on alterable degrees of freedom that are mainly provided by organic linkers or the junctions linking organic and inorganic building units. Herein, we report a new dynamic MOF whose flexibility originates from an unprecedented tailorable Mn8O38‐cluster and shows simultaneous coordination geometry changes and ligand migration that are reversibly driven by guest exchange. This provides an extra degree of freedom to the framework's deformation, resulting in three‐dimensional variations in the framework that subtly respond to varied aromatic molecules. The gas adsorption behavior of this flexible MOF was evaluated, and the selective separation of light hydrocarbons and Freon gases is achieved. [ABSTRACT FROM AUTHOR]

The design and creation of soft porous crystals combining regularity and flexibility may promote potential applications for gas storage and separation due to their deformable framework's responsiveness to external stimuli. The flexibility of metal–organic frameworks (MOFs) relies on alterable degrees of freedom that are mainly provided by organic linkers or the junctions linking organic and inorganic building units. Herein, we report a new dynamic MOF whose flexibility originates from an unprecedented tailorable Mn8O38‐cluster and shows simultaneous coordination geometry changes and ligand migration that are reversibly driven by guest exchange. This provides an extra degree of freedom to the framework's deformation, resulting in three‐dimensional variations in the framework that subtly respond to varied aromatic molecules. The gas adsorption behavior of this flexible MOF was evaluated, and the selective separation of light hydrocarbons and Freon gases is achieved. [ABSTRACT FROM AUTHOR]

In multiphoton excited fluorescence (MPEF), high‐energy upconversion emission is obtained from low‐energy excitation by absorbance of two or more photons simultaneously. In a pressure‐induced fluorochromic process, the emission energy is switched by outer pressure stimuli. Now, five metal–organic frameworks containing the same ligand with simultaneous multiphoton absorption and pressure‐induced fluorochromic attributes were studied. One‐, two‐, and three‐photon excited fluorescence (1/2/3PEF) can be achieved in the frameworks, which exhibit pressure‐induced blue‐to‐yellow fluorochromism. The performances are closely dependent with the topologies, flexibilities, and packing states of the frameworks and chromophores therein. The multiphoton upconversion performance can be intensified by pressure‐related structural contraction. Over ten‐fold increment in the 2PA active cross‐section up to 2217 GM is achieved in pressed LIFM‐114 compared with the 210 GM for pristine sample at 780 nm. [ABSTRACT FROM AUTHOR]

In multiphoton excited fluorescence (MPEF), high‐energy upconversion emission is obtained from low‐energy excitation by absorbance of two or more photons simultaneously. In a pressure‐induced fluorochromic process, the emission energy is switched by outer pressure stimuli. Now, five metal–organic frameworks containing the same ligand with simultaneous multiphoton absorption and pressure‐induced fluorochromic attributes were studied. One‐, two‐, and three‐photon excited fluorescence (1/2/3PEF) can be achieved in the frameworks, which exhibit pressure‐induced blue‐to‐yellow fluorochromism. The performances are closely dependent with the topologies, flexibilities, and packing states of the frameworks and chromophores therein. The multiphoton upconversion performance can be intensified by pressure‐related structural contraction. Over ten‐fold increment in the 2PA active cross‐section up to 2217 GM is achieved in pressed LIFM‐114 compared with the 210 GM for pristine sample at 780 nm. [ABSTRACT FROM AUTHOR]

Through dynamic spacer installation, five fluorescent metal–organic frameworks (MOFs) have been constructed based on a proto-MOF LIFM-28 and multivariate ligands as fluorophores. The emissions are tunable via insertion of fluorescent ligands, demonstrating a versatile approach for luminescence tuning by virtue of dynamic spacer installation using swing-role MOFs. [ABSTRACT FROM AUTHOR]

A series of isostructual aromatics⊂CdL2(OTs)2 (aromatics = benzene, toluene, o-xylene, m-xylene and p-xylene) supramolecular complexes were prepared based on aromatic templates. The CdL2(OTs)2 framework is stable and contains square-like hydrophobic channels. It can reversibly adsorb benzene, toluene, o-xylene, m-xylene and p-xylene in the liquid phase without the loss of its structural integrity. Furthermore, it exhibits a clear affinity for these aromatics according to the following order: xylene ＞ toluene ＞ benzene, and it effectively separates xylene/toluene/benzene mixtures in the liquid phase under ambient conditions. In addition, aromatics⊂CdL2(OTs)2 exhibits guest-dependent luminescence properties. [ABSTRACT FROM AUTHOR]