Elucidating the synergistic effect of oxygen vacancies and Z-scheme heterojunction in NU-1000/BiOCl-Ov composites towards enhanced photocatalytic degradation of tetracycline hydrochloride.

Although Z-scheme heterojunction composites have been widely studied in photocatalysis, in-depth investigation of oxygen vacancies (Ov) in the Z-scheme photocatalysts is still rare. Herein, an oxygen vacancies modified NU-1000/BiOCl-Ov composite with Z-scheme heterojunction was rationally designed and fabricated. The combination of X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) experiment verified the presence of oxygen vacancies, meanwhile the Z-scheme charge transfer across the heterojunction interface was confirmed in detail by the in situ-XPS, Kelvin probe force microscope (KPFM) studies, ultraviolet photoelectron spectroscopy (UPS), EPR radical capture experiment, as well as density functional theory (DFT) calculation.

Boosting the degradation of antibiotics peroxymonosulfate activation with a Cu-based metal-organic framework.

Highly efficient degradation of antibiotics is a huge challenge due to the extremely stable molecules and the potential for biological resistance. However, conventional degradation methods are limited to lower degradation rate, higher energy consumption and secondary pollution. Herein, we report a new Cu-based metal-organic framework (MOF), featuring classical planar trinuclear [Cu(µ-O)] clusters within the pores.

Metal-Organic Framework Based Sensors for Benzene Vapor.

Sensing of benzene vapor is a hot spot due to the volatile drastic carcinogen even at trace concentration. However, achieving convenient and rapid detection is still a challenge. As a sort of functional porous material, metal-organic frameworks (MOFs) have been developed as detection sensors by adsorbing benzene vapor and converting it into other signals (fluorescence intensity/wavelength, chemiresistive, weight or color, etc.

Quasi-open Cu(I) sites for efficient CO separation with high O/HO tolerance.

Carbon monoxide (CO) separation relies on chemical adsorption but suffers from the difficulty of desorption and instability of open metal sites against O, HO and so on. Here we demonstrate quasi-open metal sites with hidden or shielded coordination sites as a promising solution. Possessing the trigonal coordination geometry (sp), Cu(I) ions in porous frameworks show weak physical adsorption for non-target guests.

Fluorescence Enhancement of a Metal-Organic Framework for Ultra-Efficient Detection of Trace Benzene Vapor.

Indoor detection of volatile organic compounds (VOCs) concentration is necessary due to the serious toxicity hazards even at trace level. However, physisorbents usually exhibit weak interactions especially in the presence of trace concentrations of VOCs, thus exhibiting poor responsive signal. Herein, we report a new flexible metal-organic framework (MOF) that exhibits interesting pore-opening behavior after immersing in H O.

Expedient Synthesis of Dihaloalkenynes via Pd-Catalyzed Haloalkynylation Reaction.

Herein, the Pd -catalyzed construction of functionalized dihaloalkenynes from haloalkynes via a self-haloalkynylation reaction, without specialized ligands or oxidizing additives, is reported. The method tolerates a diverse range of haloalkynes, including electron-donating and electron-withdrawing functional groups, such as macrocyclic alkynols, spiro-oxy ring alkynols, and even carbazole-containing, pyrrolidine-2,5-dione-containing and silyl-protected bromoalkynes. Using an opposite lithium halide (LiX) to the haloalkyne starting material, remarkably high regio- and stereoselectivity of the haloalkynylation reaction is possible, yielding 1-bromo-2-chloroalkenyne or 2-bromo-1-chloroalkenyne products as desired.

A series of naphthalenediimide-based metal-organic frameworks: synthesis, photochromism and inkless and erasable printing.

Three new three-dimensional metal-organic frameworks were synthesized based on a naphthalenediimide derivative ligand, all of which exhibit photochromic behaviour due to the presence of the naphthalenediimide core. Interestingly, two of them possess significant colour changes under light, excellent stability, and appropriate photochromic lifetimes, thus showing potential for application in inkless and erasable printing media.

Conductive Hydrogels with Ultrastretchability and Adhesiveness for Flame- and Cold-Tolerant Strain Sensors.

Hydrogel strain sensors with extreme temperature tolerance have recently gained great attention. However, the sensing ability of these hydrogel strain sensors changes with temperature, resulting in the variety of output signals that causes signal distortion. In this study, double-network hydrogels comprising SiO nanoparticles composed of polyacrylamide and phytic acid-doped polypyrrole were prepared and applied on strain sensors with a wide sensing range, high adhesiveness, and invariable strain sensitivity under flame and cold environments.

Photochromic Metal-Organic Framework for High-Resolution Inkless and Erasable Printing.

Inkless and erasable printing as a new technology has received intense attention in reducing paper waste and environmental hazards caused by the use of large amounts of ink. However, achieving high-resolution printing by inkless and erasable printing for practical applications remains a huge challenge. Herein, a new metal-organic framework (MOF) has been synthesized, which exhibits a reversible photochromic behavior.

UV/chlorine process for degradation of benzothiazole and benzotriazole in water: Efficiency, mechanism and toxicity evaluation.

Benzothiazole (BZA) and benzotriazole (BTZ) as emerging contaminants were found persistent in aquatic environments and toxic to aquatic organisms. The degradation of BZA and BTZ by UV/chlorine was systematically investigated in this study, and the results showed that BZA and BTZ can be remarkably removed by UV/chlorine compared with UV alone and dark chlorination. The radical quenching tests showed that degradation of BZA and BTZ by UV/chlorine involved the participation of reactive chlorine species (RCS), hydroxyl radical (HO·), and UV photolysis.

Flexibility of Metal-Organic Framework Tunable by Crystal Size at the Micrometer to Submillimeter Scale for Efficient Xylene Isomer Separation.

Understanding, controlling, and utilizing the flexibility of adsorbents are of great importance and difficulty. Analogous with conventional solid materials, downsizing to the nanoscale is emerging as a possible strategy for controlling the flexibility of porous coordination polymers (or metal-organic frameworks). We report a unique flexibility controllable by crystal size at the micrometer to submillimeter scale.

Partially Fluorinated Cu(I) Triazolate Frameworks with High Hydrophobicity, Porosity, and Luminescence Sensitivity.

Solvothermal reactions of 3-methyl-5-trifluoromethyl-1,2,4-triazole (Hfmtz) with Cu(CHCOO) at 120 °C in the presence of Cl generate two partially fluorinated coordination polymers: i.e., [CuCl(fmtz)] (1 or MAF-51) and [CuCl(fmtz)] (2 or MAF-52).

Mesoporous Metal-Organic Frameworks with Exceptionally High Working Capacities for Adsorption Heat Transformation.

Pore size is one of the most important parameters of adsorbents, and mesoporous materials have received intense attention for large guests. Here, a series of mesoporous coordination polymers underlying a new framework prototype for fast expansion of pore size is reported and the profound effect of pore size on adsorption heat transformation is demonstrated. Three isostructural honeycomb-like frameworks are designed and synthesized by combining ditopic linear metal oxalate chains and triangular tris-pyridine ligands.

Cobalt(II) Magnetic Metal-Organic Framework with an Effective Kagomé Lattice, Large Surface Area, and High Spin-Canted Ordering Temperature.

To make a porous material with high magnetic ordering temperature is challenging because the low density of the material is adverse to the dense magnetic moment, a prerequisite to high-performance magnets. Herein, we report a hollow magnetic metal-organic framework (MMOF) [Co(bpdc)(tpt)] 1 (Hbpdc = 4,4'-biphenyldicarboxylic acid) with a Langmuir surface area of 1118 m/g and spin-canted long-range magnetic ordering up to 22 K. Such a high performance is owing to the unique antiferromagnetic Kagomé lattice made of ferromagnetic Co clusters and conjugated 2,4,6-tri(4-pyridinyl)-1,3,5-triazine (tpt) ligands, which is closely coupled with each other via double-interpenetration of the porous networks.

Mixed-Lanthanide Porous Coordination Polymers Showing Range-Tunable Ratiometric Luminescence for O Sensing.

Luminescent porous coordination polymers (PCPs) are emerging as attractive oxygen-sensing materials, but they are mostly based on single-wavelength luminometry. Here, we report a special mixed-lanthanide strategy for self-referenced ratiometric oxygen sensing. A series of isostructural, pure-lanthanide, or mixed-lanthanide PCPs, MCF-53(Tb/Eu), were synthesized by solvothermal reactions.

Thermal and Gas Dual-Responsive Behaviors of an Expanded UiO-66-Type Porous Coordination Polymer.

Through a modified solvothermal reaction using benzoic acid as an additive, the fcu-type framework [Zr O (OH) (edba) ] (H edba=4,4'-(ethyne-1,2-diyl)dibenzoic acid), an expanded version of UiO-66, is synthesized as high-quality single crystals, which can retain their single-crystallinity after solvent exchange and degas treatments. In situ variable-temperature single-crystal X-ray diffraction measurements show that the guest-free framework exhibits a remarkably large isotropic negative thermal expansion (α=-11.0×10  K ) as a result of the transverse vibrational bending of the long organic ligand.

High-symmetry hydrogen-bonded organic frameworks: air separation and crystal-to-crystal structural transformation.

By changing the size of a substituent group, benzotrisimidazoles can self-assembly to give a honeycomb-like (hcb) layer or a three-dimensional (10,3)-a (srs) network. While the former is highly stable and rigid with little porosity, the latter can undergo a water-induced reversible crystal-to-crystal transformation and selectively adsorb O2 over Ar and N2.

[Ni(dap)3]4[As10Cu2S18]: a new thioarsenate containing the rare [As3CuS6] cluster with mixed-valence As2+/As3+ ions.

A new mixed-valence thioarsenate(II,III) [Ni(dap)3]4-[As10Cu2S18] (1, dap = diaminopropane) has been solvothermally synthesized and structurally characterized. 1 features a new heterometallic thioarsenate [As10Cu2S18](8-) with mixed valence As(2+)/As(3+) ions, which is constructed by combination of the chair-shaped tetramer cyclo-[As4S8] and the rare heterometallic cluster [As3CuS6]. 1 is the first example of transition metal ions encapsulated within mixed-valent thioarsenates(II,III).