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Metal organic framework (MOF) materials have attracted widespread interests because of their potential application prospects in the field of heterogeneous catalysis. In this work, a cobalt-based MOF Co3-btca was developed as an efficient heterogeneous catalyst for the degradation of organic dye pollutants in water by activating peroxymonosulfate (PMS). Detailed characterizations showcased that the as-prepared nitrogen-rich Co-MOF Co3-btca possessed micron size and good stability. In the presence of both Co3-btca and PMS, the methyl violet (MV) degradation rate reached 99.78% within 9 min, while the rhodamine B (RhB) degradation rate reached 99.58% within 15 min. The effect of dye concentrations, reaction temperature, PMS and catalyst dosages on degradation reactions was studied. More importantly, successive degradation experiments demonstrated that the as-prepared Co3-btca catalyst possessed good stability with easy recycling for eliminating organic contaminants from wastewater. Radical trapping measurements confirmed that SO4−˙ and ˙OH radicals were the main active species for the removal of organic dyes. Moreover, we speculated the possible degradation mechanism of organic dyes. These features make Co3-btca a stable heterogeneous catalyst for the efficient activation of PMS in environmental remediation. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of CO2 to added‐value fuels or chemicals is a promising technology for the effective utilization of the disturbing greenhouse gas, but its economic benefit is limited either by low efficiency due to the difficulty of water oxidation or by the employment of expensive sacrificial reagents. To overcome this dilemma, herein, an effective strategy is reported for the resourceful utilization of CO2 by creating an eco‐friendly bifunctional photocatalyst to achieve CO2 photoreduction concurrent with methanol photooxidation to the uniform product of formic acid for the first time. The bifunctional photocatalyst is elaborately constructed by in situ encapsulating lead‐free double perovskite (Cs2AgBiBr6, abbreviated as CABB) nanocrystals into the pores of Fe‐based metal−organic framework (MIL‐101(Fe)). The tight contact between CABB and MIL‐101(Fe) in the resultant CABB/MIL‐101(Fe) composite facilitates the efficient spatial separation of photogenerated carriers, which leads to the division of reduction and oxidation functional units. CABB/MIL‐101(Fe) composites can unify the redox products into formic acid, reaching an impressive formation yield of 1375 μmol g−1 h−1 with a high selectivity of 97.8%. This work provides a viable strategy for the efficient photosynthesis of formic acid, promoting the cost‐effective utilization of CO2. [ABSTRACT FROM AUTHOR]

A novel 3D MOF [(Zn4O)(H2O)2(TPA)2]·8DMA (1) (H3TPA = 4,4′,4′′-nitrilotrisbenzoic acid; DMA = N,N-dimethylacetamide) with tetragonal nanochannels has been rationally obtained under solvothermal conditions using the fluorescent ligand H3TPA. MOF 1 demonstrates a unique (3,6)-connected network with nanosized square channels, displaying strong blue emission. Interestingly, 1 can be used as a fluorescent probe, which can detect nitroaromatic explosives efficiently and selectively via fluorescence quenching phenomena. As the number of –NO2 groups increase, fluorescence quenching becomes more obvious, which is maybe because the energy transfer from the electron-donating framework to electron-withdrawing nitroaromatic analytes becomes greater. Notably, the sensor is particularly sensitive to picric acid (PA), showing complete fluorescence quenching at a PA concentration as low as 30 ppm. MOF 1 can be recycled in the detection of nitroaromatic explosives with excellent recyclability. Additionally, the photo-induced electron transfer mechanism was validated through theoretical calculations for the fluorescence quenching. [ABSTRACT FROM AUTHOR]

A six-coordinated 3D metal–organic framework (MOF), [ZnK(tatab)(CH3OH)]·3DMF·4.5CH3OH (JLNU-2, JLNU = Jilin Normal University, H3tatab = 4,4′,4′′-((1,3,5-triazine-2,4,6-triyl)tris(azanediyl)) tribenzoic acid, DMF = N,N-dimethylformamide), has been purposefully constructed by combining the N-donor ligand H3tatab with aromatic π rings and d10 configuration metal Zn(ii) nitrate under solvothermal conditions. The crystal structure reveals that JLNU-2 consists of a dual-aerial-octahedral trinuclear potassium cluster and zinc building units with N–H…O hydrogen bonding, which are further bridged by N-donor multicarboxylate ligands to produce a (3,6)-connected topological net in an interesting hot-wheel state. The special hydrogen bonding strongly promotes the molecular luminescence sensitivity. The experimental results show that JLNU-2 exhibits outstanding fluorescence quenching properties via an electron transfer mechanism from the electron-rich framework to the electron-withdrawing group of nitrobenzene. The fluorescence was quenched completely in the presence of 130 ppm of nitrobenzene. After 8 cycles, the quenching efficiency was maintained at 88.9%. As a result, the MOF material is extremely well qualified to be a fluorescence sensor for the detection of nitrobenzene owing to its supreme selectivity, sensitivity, anti-interference ability and recyclability. [ABSTRACT FROM AUTHOR]

A series of isoreticular metal-organic frameworks (MOFs; NENU-511- NENU-514), which all have high surface areas and strong adsorption capacities, have been successfully constructed by using mixed ligands. NENU-513 has the highest benzene capacity of 1687 mg g−1at 298 K, which ranks as the top MOF material among those reported up to now. This NENU series has been used for adsorptive desulfurization because of its permanent porosity. The results indicate that this series has a higher adsorptive efficiency in the removal of organosulfur compounds than other MOF materials, especially NENU-511, which has the highest adsorptive efficiency in the ambient atmosphere. This study proves that the design and synthesis of targeted MOFs with higher surface areas and with functional groups present is an efficient method to enhance benzene-storage capacity and the adsorption of organosulfur compounds. [ABSTRACT FROM AUTHOR]

Herein, a novel anionic framework with primitive centered cubic (pcu) topology, [(CH3)2NH2]4[(Zn4dttz6)Zn3]⋅15 DMF⋅4.5 H2O, ( IFMC-2; H3dttz=4,5-di(1 H-tetrazol-5-yl)-2 H-1,2,3-triazole) was solvothermally isolated. A new example of a tetranuclear zinc cluster {Zn4dttz6} served as a secondary building unit in IFMC-2. Furthermore, the metal cluster was connected by ZnII ions to give rise to a 3D open microporous structure. The lanthanide(III)-loaded metal-organic framework (MOF) materials Ln3+@IFMC-2, were successfully prepared by using ion-exchange experiments owing to the anionic framework of IFMC-2. Moreover, the emission spectra of the as-prepared Ln3+@IFMC-2 were investigated, and the results suggested that IFMC-2 could be utilized as a potential luminescent probe toward different Ln3+ ions. Additionally, the absorption ability of IFMC-2 toward ionic dyes was also performed. Cationic dyes can be absorbed, but not neutral and anionic dyes, thus indicating that IFMC-2 exhibits selective absorption toward cationic dyes. Furthermore, the cationic dyes can be gradually released in the presence of NaCl. [ABSTRACT FROM AUTHOR]

A 2D, extremely stable, metal-organic framework (MOF), NENU-503, was successfully constructed. It displays highly selective and recyclable properties in detection of nitroaromatic explosives as a fluorescent sensor. This is the first MOF that can distinguish between nitroaromatic molecules with different numbers of NO2 groups. [ABSTRACT FROM AUTHOR]

A new family of heterometal-organic frameworks has been prepared by two synthesis strategies, in which IFMC-26 and IFMC-27 are constructed by self-assembly and IFMC-28 is obtained by stepwise synthesis based on the metalloligand (IFMC=Institute of Functional Material Chemistry). IFMC-26 is a (3,6)-connected net and IFMC-27 is a (4,8)-connected 3D framework. The metalloligands {Ni(H4L)}(NO3)2 are connected by binuclear lanthanide clusters giving rise to a 2D sheet structure in IFMC-28. Notably, IFMC-26-Eu x Tb y and IFMC-28-Eu x Tb y have been obtained by changing the molar ratios of raw materials. Owing to the porosity of IFMC-26, Tb3+@IFMC-26-Eu and Eu3+@IFMC-26-Tb are obtained by postencapsulating TbIII and EuIII ions into the pores, respectively. Tunable luminescence in metal-organic frameworks is achieved by the two kinds of doping methods. In particular, the quantum yields of heterometal-organic frameworks are apparently enhanced by postencapsulation of LnIII ions. [ABSTRACT FROM AUTHOR]

JLNU-7 with a (4,6)-connected 3D network has been hydrothermally synthesized and characterized in detail. JLNU-7 displays characteristic Type-I sorption isotherm for microporous materials. The blue-emitting JLNU-7 was synthesized as a platform for encapsulating yellow-emitting [Ir(ppy) 2 (bpy)][PF 6 ], namely IrIII@JLNU-7. IrIII@JLNU-7 displays white light emission with Commission International de I'Eclairage (CIE) coordinate of (0.323, 0.298) and high quantum yield up to 11.9%. • JLNU-7 with a (4,6)-connected 3D network has been hydrothermally synthesized and characterized in detail. • JLNU-7 displays characteristic Type-I sorption isotherm for microporous materials. • The high performance white-light-emitting of Ir III @JLNU-7 will be applied in the practical lighting. A luminescent MOF [(Zn 4 O)(L)(2,6-naphthalic acid)]·4H 2 O·DMF (JLNU-7 , JLNU = Jilin Normal University, H 4 L = methanetetra(tetrakis[4-(carboxyphenyl)oxamethyl]-methane acid) has been hydrothermally synthesized and carefully characterized. The prepared JLNU-7 displayed permanent porosity in the air. Here we select a reasonable strategy to achieve efficient white-light emission by the combination of blue emission from JLNU-7 and yellow emission from [Ir(ppy) 2 (bpy)][PF 6 ] (IrIII, Hppy = 2-phenylpyridine, bpy = 2,2ʹ-bipyridine). The blue-emitting JLNU-7 was synthesized as a platform for encapsulating yellow-emitting IrIII complex, namely IrIII@JLNU-7. IrIII@JLNU-7 displays white light emission with Commission International de I'Eclairage (CIE) coordinate of (0.323, 0.298) and high quantum yield up to 11.9%. This strategy may promote the development and application of white phosphors with high performance in the practical lighting. [ABSTRACT FROM AUTHOR]

Metal-organic framework (MOF) materials have highly sought after in electromagnetic materials and functional devices, due to the unique three-dimensional structure and electronic state. Herein, the tailoring strategy of MOF materials, including MOF precursors and carbonized derivatives, is combed for high-efficiency microwave absorbers. The design idea from microstructure to electromagnetic response is constructed. Based on these theories, the current research progress about MOF-based absorbers is presented, and the effect of microstructure tailoring to electromagnetic property and microwave absorption is revealed. In addition, the application of MOF materials in functional device is outlined. Finally, the current challenges for MOF materials and devices are overviewed, and the future development is expected. Image 103774 Tailoring the microstructure of MOF materials can effectively tune electromagnetic property and obtain great microwave absorbers and devices. [ABSTRACT FROM AUTHOR]

In this paper, a stable Cd-MOF 1 has been successfully designed and synthesized by solvothermal reaction and characterized in detail. The framework of the Cd-MOF can maintain intact in the air, water, acidic/basic aqueous solutions (pH = 1∼13) and common organic solvents. The complex 1 possesses outstanding chemical stability in aqueous solution. Notably, MOF 1 can be used as a fluorescent probe for selective, sensitive and recyclable sensing of Fe3+ in water. [Display omitted] • A luminescent Cd-MOF has been synthesized by solvothermal method and characterized by a series of modern tools. • The Cd-MOF 1 exhibits excellent chemical stability in aqueous solution. • The MOF 1 can be used as a fluorescent probe for selective, sensitive and recyclable sensing of Fe3+ in water. A new stable Cd(II)-MOF [Cd(PBA)(pic)(H 2 O)]·H 2 O·0.5DMA (1) (HPBA = 4-(pyridin-4-yl) benzoic acid, Hpic = 2-picolinic acid, DMA = N, N'-dimethylacetamide) has been successfully constructed by solvothermal condition and characterized in detail. MOF 1 exhibits excellent chemical stability in water, which provides possible for sensing in water. The luminescent spectra demonstrate different to different metal cations. Notably, Fe3+ causes the highest fluorescence quenching, and the quenching efficiency is up to 96% at a concentration of 10−3 M Fe3+ in aqueous solution. Additionally, there was no obvious change in fluorescent quenching efficiency after 5 sensing cycles. Therefore, MOF 1 is expected to be used as a fluorescent probe for sensing Fe3+ in water with high selectivity, sensitivity, and recyclability. [ABSTRACT FROM AUTHOR]