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Improving proton conductivity and fabricating viable metal‐organic frameworks (MOFs) based proton exchange membranes (PEMs) are central issues exploiting electrolyte MOFs. We aim to design multivariate flexibility synergistic strategy to achieve Flexible MOFs (FMOFs) with high conductivity at a wide range of humidity. In situ powder X‐ray diffraction (PXRD) and temperature‐dependent Fourier transform infrared spectra (FT‐IR) prove the synergistic self‐adaption between dynamic torsion of alkyl sulfonic acid and dynamic breathing of FMOF, forming a continuous hydrogen‐bonding networks to maintain high conductivity. Based on the convincing proton conductivity, we construct a series of long‐term durable MOF‐based PEMs that serve as a bridge between MOF and fuel cell. Consequently, the membrane electrode assembly (MEA) of the flexible PMNS1‐40 exhibits a maximum single‐cell power density of 34.76 mW cm−2 and hopefully opens doors to evaluate the practical application of proton‐conducting MOFs in direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

Improving proton conductivity and fabricating viable metal‐organic frameworks (MOFs) based proton exchange membranes (PEMs) are central issues exploiting electrolyte MOFs. We aim to design multivariate flexibility synergistic strategy to achieve Flexible MOFs (FMOFs) with high conductivity at a wide range of humidity. In situ powder X‐ray diffraction (PXRD) and temperature‐dependent Fourier transform infrared spectra (FT‐IR) prove the synergistic self‐adaption between dynamic torsion of alkyl sulfonic acid and dynamic breathing of FMOF, forming a continuous hydrogen‐bonding networks to maintain high conductivity. Based on the convincing proton conductivity, we construct a series of long‐term durable MOF‐based PEMs that serve as a bridge between MOF and fuel cell. Consequently, the membrane electrode assembly (MEA) of the flexible PMNS1‐40 exhibits a maximum single‐cell power density of 34.76 mW cm−2 and hopefully opens doors to evaluate the practical application of proton‐conducting MOFs in direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

The field of post‐synthesis modification has aroused widespread concern from diverse perspectives, including chemistry, biology, and material science. Post‐synthesis modification can introduce rich functionality into metal–organic frameworks (MOFs) without destroying the main structure of MOFs. Based on this research status, a series of lanthanide metal–organic frameworks ([Ln2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA, Ln = Pr, Nd, Sm, Eu, Gd and Tb, NH2‐BDC = 2‐aminoterephthalic acid, DMA = N,N‐Dimethylacetamide) with 3D network structures, are synthesized by hydrothermal synthesis. Due to the presence of uncoordinated amino groups in the ligands, a series of post‐synthesis modified compounds are successfully synthesized through aldimine condensation reaction. Based on the good fluorescence properties and stable structure of coordination polymers and post‐synthesis modified compounds in water or organic solvents, they are able to be used as potential fluorescence sensor for the detection of Th4+, UO22+, and Cr2O72−, and the calculation result shows that the post‐synthesis modified compounds are more sensitive to the detection of analytes (Th4+, UO22+ and Cr2O72−) than coordination polymers. In addition, the MOF membrane prepared by self‐assembly of [Eu2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA and ternary soap‐free copolymer (VAc‐AA‐BA) emulsion can be used first for detecting aldehyde vapors. [ABSTRACT FROM AUTHOR]

Herein we report two new TPE‐based 3D MOFs, that is, Sr‐ETTB and Co‐ETTB (TPE=Tetraphenylethylene, H8ETTB=4′,4′′′,4′′′′′,4′′′′′′′‐(ethene‐1,1,2,2‐tetrayl)tetrakis(([1,1′‐biphenyl]‐3,5‐dicarboxylic acid))). Through tailoring outer shell electron configurations of SrII and CoII cations, the fluorescence intensity of the MOFs is tuned from high emission to complete non‐emission. Sr‐ETTB with strong blue fluorescence shows reversible fluorescence variations in response to pressure and temperature, which is directly related to the reversible deformation of the crystal structure. In addition, non‐emissive Co‐ETTB counterpart exhibits a turn‐on fluorescent enhancement under the stimulation of analyte histidine. In the process, TPE‐cored linkers in the MOFs are released through competitive coordination substitution and subsequently reassembled to perform aggregation‐induced luminescence behavior originated from the organic linkers. [ABSTRACT FROM AUTHOR]

Herein we report two new TPE‐based 3D MOFs, that is, Sr‐ETTB and Co‐ETTB (TPE=Tetraphenylethylene, H8ETTB=4′,4′′′,4′′′′′,4′′′′′′′‐(ethene‐1,1,2,2‐tetrayl)tetrakis(([1,1′‐biphenyl]‐3,5‐dicarboxylic acid))). Through tailoring outer shell electron configurations of SrII and CoII cations, the fluorescence intensity of the MOFs is tuned from high emission to complete non‐emission. Sr‐ETTB with strong blue fluorescence shows reversible fluorescence variations in response to pressure and temperature, which is directly related to the reversible deformation of the crystal structure. In addition, non‐emissive Co‐ETTB counterpart exhibits a turn‐on fluorescent enhancement under the stimulation of analyte histidine. In the process, TPE‐cored linkers in the MOFs are released through competitive coordination substitution and subsequently reassembled to perform aggregation‐induced luminescence behavior originated from the organic linkers. [ABSTRACT FROM AUTHOR]

Two new isostructural 3D lanthanide-organic frameworks [H2N(Me)2] [Ln3(OH)(bpt)3(H2O)3] (DMF)2⋅(H2O)4 ( 1-Ln; Ln=Sm and Eu) with a 1D channel (25 Å) have been successfully assembled from the rare trinuclear [Ln3(OH)(COO)9] clusters and biphenyl-3,4′,5-tricarboxylic acid (H3bpt) and exhibit high stability towards water in the pH range 3-10. MOF 1-Eu is a promising luminescent probe for sensing Fe3+ in aqueous solution and is also selective towards rhodamine B (RhB) with a superior adsorption capacity of 735 mg g−1, which is the highest among the reported Ln-MOFs for RhB removal so far. Periodic DFT calculations further confirmed the selective adsorption of rhodamine B over other dyes. [ABSTRACT FROM AUTHOR]

A metal-organic framework (MOF) based on (bpy)Re(CO)3Cl-containing elongated dicarboxylate ligands and Zr6(µ3-O)4(µ3-OH)4 clusters was synthesized and used as an effective single-site catalyst to photochemically reduce carbon dioxide to carbon monoxide and formate and to provide mechanistic insights into the photocatalytic CO2 reduction process. [ABSTRACT FROM AUTHOR]

Two microporous complexes, [Zn(TATAB)(OCH3)] ⋅2 H3O+ ( 1; TATAB=4,4′,4′′-[(1,3,5-triazine-2,4,6-triyl)tris(azanediyl)]tribenzoic acid), [Cu1.5(μ2-O)TATAB*] ( 2; TATAB*=4,4′-{[6-(dimethylamino)-1,3,5-triazine-2,4-diyl]bis(azanediyl)}dibenzoic acid) have been synthesized and characterized by elemental analysis, IR spectroscopy, UV absorption spectroscopy, and thermogravimetric analysis, and by powder XRD and single-crystal XRD analysis. Structural analyses revealed that complex 1 possesses a 3D porous framework with uncoordinated water molecules trapped in the pores; the dimensions of the channels are approximately 29.2×12.3 Å2. Complex 2 has a 3D microporous network structure. In addition, the surface photovoltage and photocatalytic activities were also studied. The photocatalytic properties of the two complexes were investigated by the decomposition of methylene blue under UV and visible-light irradiation. The results revealed that 2 possessea a higher photocatalytic activity than 1 under UV or visible-light irradiation. The potential semiconductor and dye degradation properties of complexes 1 and 2 may be widely applied in the fields of chemical semiconductors and environmental protection in the future. [ABSTRACT FROM AUTHOR]

A series of 4f-5f heteronuclear metallic complexes were synthesized by a hydrothermal route from mixtures of uranyl acetate, lanthanide nitrate, and 1,2,4,5-benzenetetracarboxylic acid (H4BTA) in an aqueous system. Single-crystal X-ray analysis revealed that the thirteen UO2-Ln-BTA complexes ([(UO2)1.5Ln(C10O8H2)1.5(H2O) x]⋅ y H2O; Ln=La ( 1), Ce ( 2), Pr ( 3), Nd ( 4), Sm ( 5), Eu ( 6), Gd ( 7), Tb ( 8), Dy ( 9), Ho ( 10), Er ( 11), Tm ( 12), Yb ( 13); x=6 for 1- 4, x=5 for 5- 13; y=0 for 4, y=1 for 3, y=2 for 2, y=3 for 5, 9, 10, 12, 13, y=4 for 1, 6, 7, 8, 11) are isomorphous with three-dimensional structures. For the purpose of developing potential applications of the UO2-Ln-BTA complexes, we investigated their surface photovoltage and photocatalytic properties. In addition, the thermogravimetric analysis and photoluminescent properties of these complexes were also studied in detail. [ABSTRACT FROM AUTHOR]

Reducing the level of sulfur content in fuel oils has long been desired for environmental reasons. Polyoxometalates (POMs) can act as catalysts to remove sulfur-containing heterocyclic compounds by the process of oxidative desulfurization under mild conditions. However, one key obstacle to the development of POM-based catalysts is the poor solubility of POMs in the overall nonpolar environment. We report a novel strategy for the introduction of catalytically active POMs into nonpolar reaction systems by encapsulating the inorganic catalyst within the pores of a metal-organic framework structure in which the organic ligands act as hydrophobic groups. The nanocrystalline catalysts, obtained rapidly and conveniently by both solution and mechanochemical synthesis, showed remarkable activities in catalytic oxidative desulfurization reactions in both a model diesel environment and in real diesel wherein dibenzothiophene was converted rapidly and quantitatively into dibenzothiophene sulfone. [ABSTRACT FROM AUTHOR]