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Tetracycline (TC) is a commonly used antibiotic that has gained wide spread notoriety owing to its high environmental risks. In this study, rich carbonyl-modified carbon-coated Fe 0 was obtained by pyrolysis of MIL-100(Fe) in an Ar atmosphere, and used to activate peroxymonosulfate (PMS) for the degradation of tetracycline in water. The roles of Fe 0 , carbon and surface carbonyl on PMS activation were investigated. Fe 0 continuously activated PMS, acted as a sustained-release source of Fe 2+ , and could effectively activate PMS to produce SO 4 •- , O 2 •- and •OH. Carbon was found to do responsible for electron transportation during the activation of PMS and slow down the oxidation of Fe 0 . The carbonyl group on the carbon surface layer was the active site of 1 O 2 , which explains the enhanced performance for TC degradation. When Ca = 0.1 g/L and C 0 = 0.4 mM, TC degradation rate reached 96%, which was attributed to the synergistic effect of radicals (i.e., SO 4 •- , O 2 •- , •OH) and non-radical (i.e., 1 O 2 ). Finally, the degradation pathway was proposed by combining density functional theory (DFT) calculations with liquid chromatography-mass spectrometry (LC-MS), toxicities of the intermediate products were also evaluated. All results show that carbonyl-modified carbon-coated Fe 0 possesses promising capacity for the removal of antibiotics from water., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Discrimination of physically similar molecules by porous solids represents an important yet challenging task in industrially relevant chemical separations. Precisely controlled pore dimension and/or tailored pore surface functionality are crucial to achieve high‐efficiency separation. Metal‐organic frameworks (MOFs) are promising candidates for these challenging separations in light of their structural diversity as well as highly adjustable pore dimension/functionality. We report here a microporous, ftw‐type Zr‐based MOF structure, HIAM‐410 (HIAM=Hoffmann Institute of Advanced Materials), built on hexanuclear Zr6 cluster and pyrene‐1,3,6,8‐tetracarboxylate (ptc4−). Its crystallographic structure has been determined using continuous rotation electron diffraction (cRED) technique combined with Rietveld refinement against powder X‐ray diffraction data, aided by low‐dose high‐resolution transmission electron microscopy (HRTEM) imaging. The compound features exceptional framework stability that is comparable to the prototype MOF UiO‐66. Interestingly, the linker vacancies in the pristine MOF structure could be partially restored by post‐synthetic linker insertion. Its separation capability of hexane isomers is enhanced substantially upon the linker vacancy engineering. The restored structure exhibits efficient splitting of monobranched and dibranched hexane isomers at both room temperature and industrially relevant temperature. [ABSTRACT FROM AUTHOR]

The full separation of alkane isomers as a function of different degrees of branching remains a daunting challenge due to its stringent requirement with respect to pore dimensions of the adsorbents. In this work, we report a novel microporous coordination network built on calcium (II) and chloranilate. The compound has a flexible framework and exhibits temperature‐dependent adsorption behavior toward hexane isomers. At 30 °C, it accommodates substantial amounts of linear and monobranched hexanes but fully excludes their dibranched isomer, and at elevated temperatures such as 150 °C, it acts as a splitter for linear and branched alkanes. Its capability of efficient discrimination of hexane isomers as a function of branching is verified by experimental breakthrough measurements. Ab initio calculations have uncovered the underlying selective size‐exclusion separation mechanism. [ABSTRACT FROM AUTHOR]

We report here the self-assembly of a she-type zirconium-based metal–organic framework with discrete hexanuclear Zr-oxo clusters residing inside its pore windows. The overall structure features microporosity showing preferential adsorption of Xe over Kr. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) feature intrinsically structural diversity and high tunability with respect to porosity and functionality. By practice of reticular chemistry, the pore size, pore shape, and pore surface chemistry of MOFs can be systematically and precisely tuned. MOFs with ftw topology represent an extensively studied family for which reticular chemistry has been well implemented. In this article, advances in the development of ftw-type MOFs and their related applications are reviewed. In particular, we focus on the tuning of pore size and pore shape by ligand design as well as SBU modification for targeted applications. In addition, the existing challenges and possible future directions of this important research field will be briefly discussed. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) provide an attractive platform for designing and synthesizing photoactive hybrid materials for photochemical reactions. We report here the utilization of a new visible-light responsive indium MOF for inducing the atom transfer radical polymerization (ATRP) of methacrylate monomers, where well-designed polymers with controlled molecular weights, narrow molecular weight distribution and high retention of chain-end groups have been prepared. The kinetics study reveals that the MOF-mediated ATRP shows characteristics of controlled radical polymerization (CRP). Besides, the polymerization can be easily regulated by light. Furthermore, the heterogeneous MOF can be easily recovered from the reaction and recycled for the photopolymerization. This study has involved photoactive MOFs materials into a new photochemical reaction of polymer synthesis. [ABSTRACT FROM AUTHOR]

A novel visible light responsive metal–organic framework (MOF) with a pillared-layer structure has been constructed from photoactive anthracene derived bipyridine. The as-prepared MOF was studied by single crystal X-ray diffraction, steady-state fluorescence, and electron paramagnetic resonance and so on. Studies reveal the visible light induced free radical formation of the bipyridine pillars in the MOF structure. Consequently, the promising photocatalytic reaction of atom transfer radical polymerization for methacrylate monomers was performed upon the utilization of the MOF material as a photosensitizer to reduce the copper catalyst via electron transfer. It has been demonstrated that the reaction shows characteristics of controlled radical polymerization and the prepared polymers show narrow molecular weight distributions and high retention of chain-end activities. Moreover, the photopolymerization can be easily manipulated by light switching. [ABSTRACT FROM AUTHOR]