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Newporous metal–organic framework (MOF) films based onthe flexible ligand 1,3,5-tris[4-(carboxyphenyl)oxamethyl]-2,4,6-trimethylbenzene(H3TBTC) were fabricated on α-Al2O3substrates under solvent thermal conditions. The factorsaffecting the fabrication of films, such as the temperature of pre-activationand the dosage of the reagents, were investigated. Tuning the subtlefactors on film fabrications, a series of MOF thin films with differentmorphologies and grain sizes were prepared. The morphology and grainsize of the films are monitored by scanning electron microscopy (SEM).X-ray diffraction (XRD) and attenuated total reflection infrared (ATR–IR)were also used to characterize the MOF films. The results indicatethat the temperature of pre-activation and the dosage of the reagentsare the key parameters during the process of film formation. The propertiesof the films, especially the sensing and sorption behavior, have beenstudied by an optical digital cameral and ultraviolet–visible(UV–vis) spectra. The evidence shows that the films are sensitiveto small organic molecules, such as methanol and pyridine. Meanwhile,the films can adsorb small dye molecules. Thus, the films may havepotential applications in either organic vapor sensing or storageof small dye molecules. [ABSTRACT FROM AUTHOR]

A chiral supramolecular architecture, [Cu2(4,4′-bipy)2(sala)2]n·4.5nH2O (1) (sala=N-(2-hydroxybenzyl)-l-alanine anion), has been synthesized by the reaction of Cu(NO3)2·2H2O with 4,4′-bipyridine (4,4′-bipy) and N-(2-hydroxybenzyl)-l-alanine (H2sala) in basic ethanol/aqueous solution. X-ray single crystal diffraction analysis reveals that complex 1 has a 3D extended structure in which the mononuclear anions [Cu(sala)2]2- are bonded to [Cu(4,4′-bipy)2]2+ cations through Cu–O bond at a distance of 2.528Å. One Cu(II) center is in lengthened octahedral geometry and another one is in planar square environment. The cyclic voltammetry shows that two Cu(II) centers have different electrochemical properties. [Copyright &y& Elsevier]

CO 2 electroreduction (CO 2 RR) to generate valuable chemicals in acidic electrolytes can improve the carbon utilization rate in comparison to that under alkaline conditions. However, the thermodynamically more favorable hydrogen evolution reaction under an acidic electrolyte makes the CO 2 RR a big challenge. Herein, robust metal phthalocyanine(Pc)-based (M = Ni, Co) conductive metal-covalent organic frameworks (MCOFs) connected by strong metal tetraaza[14]annulene (TAA) linkage, named NiPc-NiTAA and NiPc-CoTAA, are designed and synthesized to apply in the CO 2 RR in acidic electrolytes for the first time. The optimal NiPc-NiTAA exhibited an excellent Faradaic efficiency (FE CO ) of 95.1% and a CO partial current density of 143.0 mA cm -2 at -1.5 V versus the reversible hydrogen electrode in an acidic electrolyte, which is 3.1 times that of the corresponding metal-organic framework NiPc-NiN 4 . The comparison tests and theoretical calculations reveal that in-plane full π-d conjugation MCOF with a good conductivity of 3.01 × 10 -4 S m -1 accelerates migration of the electrons. The NiTAA linkage can tune the electron distribution in the d orbit of metal centers, making the d-band center close to the Fermi level and then activating CO 2 . Thus, the active sites of NiPc and NiTAA collaborate to reduce the *COOH formation energy barrier, favoring CO production in an acid electrolyte. It is a helpful route for designing outstanding conductive MCOF materials to enhance CO 2 electrocatalysis under an acidic electrolyte., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Electrochemical reduction of CO 2 to multicarbon (C 2+ ) products with added value represents a promising strategy for achieving a carbon-neutral economy. Precise manipulation of the catalytic interface is imperative to control the catalytic selectivity, particularly toward C 2+ products. In this study, a unique Cu/UIO-Br interface is designed, wherein the Cu(111) plane is co-modified simultaneously by Br and O from UIO-66-Br support. Such Cu/UIO-Br catalytic interface demonstrates a superior Faradaic efficiency of ≈53% for C 2+ products (ethanol/ethylene) and the C 2+ partial current density reached 24.3 mA cm -2 in an H-cell electrolyzer. The kinetic isotopic effect test, in situ attenuated total reflection Fourier transform infrared spectroscopy and density functional theory calculations have been conducted to elucidate the catalytic mechanism. The Br, O co-modification on the Cu(111) interface enhanced the adsorption of CO 2 species. The hydrogen-bond effect from the doped Br atom regulated the kinetic processes of * H species in CO 2 RR and promoted the formation of * COH intermediate. The formed * COH facilitates the * CO- * COH coupling and promotes the C 2+ selectivity finally. This comprehensive investigation not only provides an in-depth study and understanding of the catalytic process but also offers a promising strategy for designing efficient Cu-based catalysts with exceptional C 2+ products., (© 2024 Wiley‐VCH GmbH.)

Temperature plays a crucial role in both scientific research and industry. However, traditional temperature sensors, such as liquid-filled thermometers, thermocouples, and transistors, require contact to obtain heat equilibrium between the probe and the samples during the measurement. In addition, traditional temperature sensors have limitations when being used to detect the temperature change of fast-moving samples at smaller scales. Herein, the carbon quantum dots (C-QDs) functionalized metal-organic framework (MOF) composite film, a novel contactless solid optical thermometer, has been prepared via electrophoretic deposition (EPD). Instead of terephthalic acid (H 2 BDC), 1',2',4',5'-benzenetetracarboxylic (H 4 BTEC) acid was employed to construct a UiO-66 framework to present two uncoordinated carboxylic groups decorated on the pore surface. The uncoordinated carboxylic groups can generate negative charges, which facilitates the deposition of film on the positive electrode during the EPD process. Moreover, UiO-66-(COOH) 2 MOFs can absorb C-QDs from the solution and prevent C-QDs from aggregating, and the well-dispersed C-QDs impart fluorescence characteristics to composites. As-synthesized composite film was successfully used to detect temperature change in the range of 97-297 K with a relative sensitivity up to 1.3% K -1 at 297 K.