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A recycled solvent-based green synthesis strategy for 2D/3D zeolitic imidazolate frameworks (ZIFs) has been developed to produce functional nanoporous carbons (NPCs) with tuneable morphology, graphitization, N-doping and high porosity via direct pyrolysis. These tailored NPCs show superior supercapacitance performance over typical NPC derived from MOFs and chemical activation/template-directed methods. [Display omitted] • Two important aspects of green synthesis and improved supercapacitance are reported. • A green synthesis route for ZIF-8 via recycling mother liquors (RMLs) is developed. • Rod-/sheet-/polyhedral-like 2D/3D microstructures are produced with RMLs. • 2D/3D NPCs deliver excellent capacitance values and device-level performance. Carbonized metal–organic frameworks (MOFs)-based nanoporous carbon materials (NPCs) offer attractive activities in electrochemical energy conversion and storage (EECS) applications; however, there is the need for scalable MOFs production under reduced energy/environmental impact. This study reports a green synthesis route for model zeolitic imidazolate framework (ZIF-8) materials via recycling methanol-based mother liquors (ZIF-RML x) under room temperature stirring and their carbonized materials (CZC-RML x) for high-performance supercapacitors. Series of ZIF-RML x samples produced in four recycles offer rod-/sheet-/polyhedral-like 2D/3D microstructures with tuneable internal and external framework and morphological features. Accordingly, CZC-RML x , obtained by direct pyrolysis, with high microporosity and surface area of 1500 m2 g−1 deliver excellent capacitance values of 200–340 F g−1, compared to typical MOFs-derived or chemically activated/templated NPCs, produced via extended chemical processing. Structure-relevant and comparative performance analysis reveal insights for improved charge storage and carbonization-dependent graphitization, nitrogen-doping and microporosity-controlled capacitance characteristics in the CZC-RML x over typical NPCs in literature. The device-level performance with a long-term durability over 21,000 cycles is demonstrated. The practical potential of CZC-RML x is further evaluated by fabricating solid-state cells and their parallel and series circuit combinations result in overall capacitance and voltage boost to 450 F g−1 and 2.4 V, respectively. [ABSTRACT FROM AUTHOR]

SnO 2 has a high specific capacity, low price, and a wide range of sources, but the anode material made from SnO 2 is extremely unstable due to volume expansion. In this work, SnO 2 nanoparticles were prepared using Sn-MOF as the precursor and compounded with sunflower seed shell porous carbon (SSSC) in a solvothermal manner to obtain a high-performance lithium-ion battery anode. The size of SnO 2 nanoparticles prepared using Sn-MOF as the precursor is uniform, only 10–20 nm, which can fully alleviate the volume expansion of SnO 2. On this basis, MOF-SnO 2 is anchored onto the porous carbon of the sunflower seed shell, which can provide more lithium insertion sites and further inhibit the volume expansion of SnO 2. The composite anode in this article has a stable specific capacity of 1050.8 mAh g−1 after 100 cycles at a magnification of 0.2C and a stable specific capacity of 512.9 mAh g−1 after 100 cycles at a magnification of 2C. [Display omitted] • SnO 2 nanoparticles were prepared by using tin-based metal organic framework as template. • SnO 2 nanoparticles composited with sunflower seed shell porous carbon were used as anode materials. • The composite material maintains 1050.2 mAh g–1 after 100 cycles at 0.2 C for LIB. [ABSTRACT FROM AUTHOR]

In this paper, two 3D anionic metal-organic frameworks, [(CH3CH2)2NH2]·[Zn(BTC)1/3(PyC)]·1/2CH3CN·2H2O (NKU-102) and [(CH3CH2)2NH2]·[Zn2(BTC) (PyC)]·1.5H2O·DEF (NKU-103), were constructed from the same reaction system at different temperature. Though both are of anionic framework, NKU-102 possesses a sealed 3D framework based on octahedral cage and shows negligible adsorption capacity of organic dyes, whereas NKU-103 features an open triangular microchannel surrounded by two types of helical chains, and thus exhibits outstanding size-selective adsorption toward small cationic organic dyes. [ABSTRACT FROM AUTHOR]

By assembling CoII ions and a combination of 5-(4-pyridyl)tetrazole (4-ptz) and formate ions, two distinct metal-organic frameworks, [Co3(4-ptz)5(HCOO)(H2O)2] and [Co3(4-ptz)4(dmf)2(HCOO)2 ] (dmf= N, N′-dimethylformamide), were synthesized. They were both characterized by single-crystal X-ray diffraction, IR spectroscopy, thermogravimetric analysis, and powder X-ray diffraction. Structural analyses revealed that by slightly modulating the coordination environment of the trinuclear cobalt cluster, two complexes were formed featuring unusual six-connected nets reminiscent of a pyrazole-type linear trinuclear cobalt cluster as compared with the classic eight-connected bcu topology. In addition, [Co3(4-ptz)5(HCOO)(H2O)2] interacted strongly with CO2, with an adsorption enthalpy of 29.2 kJ mol−1, and in a selectivity study, the uptake ratios of CO2/N2 (from a 15:85 mixture) and CO2/CH4 (50:50 mixture) were 77.6 and 37.7, respectively. Magnetic studies on both complexes revealed weak antiferromagnetic coupling between the CoII ions. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are a class of nanoporous materials. The development of efficient and environmentally friendly methods for activating MOFs is of great significance for its industrial application. In this work, nanoscale magnetic core-shell Cu-BTC@Fe 3 O 4 was prepared through a secondary growth strategy. The effects of different activation solvents (dichloromethane and ethanol, respectively) and temperatures on the surface area, pore structures and the adsorption of xylene isomers on Cu-BTC@Fe 3 O 4 were investigated. Ethanol as an activation solvent could more easily displace the precursors remaining in the channels of Cu-BTC@Fe 3 O 4 than dichloromethane, while the temperature change has no significant influence on the pore structure. The adsorption separation of xylene isomers on Cu-BTC@Fe 3 O 4 composite materials was studied using the batch vapor-phase adsorption, and liquid-phase breakthrough experiments. The activated Cu-BTC@Fe 3 O 4 (CH 2 Cl 2 -200 ​°C ​− ​C 2 H 5 OH) material has the highest adsorption capacity of 210.26 ​mg ​g−1 for p -xylene (p X). Cu-BTC@Fe 3 O 4 (C 2 H 5 OH) and Cu-BTC@Fe 3 O 4 materials have excellent adsorption capacity for m -xylene (m X), with the values of 200.19 ​mg ​g−1 and 219.63 ​mg ​g−1, respectively, which is about 4 times higher than that of Cu-BTC@Fe 3 O 4 (CH 2 Cl 2). The adsorption capacity sequence of xylene on Cu-BTC@Fe 3 O 4 (C 2 H 5 OH) and Cu-BTC@Fe 3 O 4 materials is m -xylene (m X) ​> ​ p -xylene (p X) ​> ​ o -xylene (o X), and that of other materials is p X ​> ​ m X ​> ​ o X. Nanoscale magnetic core-shell Cu-BTC@Fe 3 O 4 was prepared through a secondary growth strategy towards the adsorption separation of xylene isomers. [Display omitted] • Nanoscale magnetic core-shell Cu-BTC@Fe 3 O 4 was prepared through a secondary growth strategy. • The effects of different activation solvents and temperatures on the xylene isomers adsorption of Cu-BTC@Fe 3 O 4 were studied. • Using ethanol as an activation solvent could more easily displace the precursors remaining in the channels of Cu-BTC@Fe 3 O 4. [ABSTRACT FROM AUTHOR]

A novel decorated metal–organic polyhedron (MOP) based metal–organic framework with a unique 4,9-connected network is successfully constructed, which displays a relatively strong interaction toward H2 and CO2 probably due to the existence of open metal sites in the secondary building units. [ABSTRACT FROM AUTHOR]

Upon solvothermal reactions between Cd(ii) salt and 5-pyridyl-tetrazolate (4-Ptz) under different reaction conditions, three new Cd(ii) metal–organic frameworks (MOFs), namely [Cd3(4-Ptz)5(H2O)2(μ3-OH)·3DMA·5H2O·CH3OH]n (1), [Cd5(4-Ptz)8(CH3OH)2(μ3-OH)2·2DMA·4H2O·3CH3OH]n (2) and [{Cd9(4-Ptz)14(AC)2(μ3-OH)2(H2O)4}·8DMA·H2O·3CH3OH]n (3), were synthesized based on different highly connected secondary building units (SBUs). In the presence of triethylamine, 1 was constructed based on an 8-connected triangular trinuclear Cd3 SBU and exhibits a three-dimensional framework, while 2 was generated upon the addition of HCl, assembled through a close packing of the octahedron cages consisting of unprecedented 12-connected 4-Ptz bridged Cd5 SBUs and thus showing high thermal and chemical stability. For generating 3, two different kinds of Cd3 SBUs, including an 8-connected triangular SBU and a 10-connected linear SBU, were constructed and further integrated into a distorted octahedron-based net under the addition of both triethylamine and NaCl. In addition to the structural analysis, we also focused on the investigation of gas adsorption and solid-state fluorescence properties of 2. [ABSTRACT FROM AUTHOR]

Two isomorphic metal-organic frameworks, [Co 2 (4-Ptz) 2 (BDC)(DMA)] n ( 1 ) and [Co 2 (4-Ptz) 2 (2-NH 2 -BDC)(DMA)] n ( 2 ) (4-Ptz=5-(4-Pyridyl)tetrazole, H 2 BDC=Terephthalic Acid, 2-NH 2 -H 2 BDC=2-Aminoterephthalic Acid, DMA=N,N-dimethylacetamide), have been successfully constructed through solvothermal reactions. Crystallographic data analysis reveals a binuclear Co(II) cluster-based structure for 1 and 2 , which were constructed by bridging two neighboring Co(II) ions with teterazole rings of 4-Ptz ligand together with one DMA oxygen atom. Simplifying Co 2 cluster as a 6-connecting node, complexes 1 and 2 reveal bcu-6 net. The CO 2 adsorption isotherms measurement at 273 K manifests higher adsorption quantities for 2 (33.8 cm 3 /g) than 1 (26.2 cm 3 /g), which was attributed to the introduction of NH 2 -group in 2 . [ABSTRACT FROM AUTHOR]

Two highly porous metal–organic frameworks are successfully constructed through the assembling of Co/Ni ions and mixed ligands. From the contribution of the uncoordinated tetrazolate N atoms of the ligand the two complexes show high CO2 adsorption capacities, serving as potential CO2 adsorption materials. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), a sub-class of well-known coordination polymers, are assorted multidimensional materials that can be employed as photocatalysts for the decomposition of aromatic dyes present in wastewater discharge. Herein, two new Cd(II) MOFs [Cd7(L)4(μ2-OH)2(H2O)4(bbi)3] (1) and [Cd3(L)2(bbm)2] (2) (H3L = 3-(4-carboxyphenoxy)-5-methylbenzoic acid, bbi = 1,4-di(1H-imidazol-1-yl)butane and bmp = 1,3-bis(2-methylimidazolyl)pentane) have been synthesized and characterized. Single-crystal X-ray diffraction analysis reveals that 1 possesses a 3D (3,16)-connected pillar-bilayer network with a {32·4}2{38·450·534·624·74} topology and comprises [Cd7(COO)14] SBUs. Meanwhile, 2 exhibits a 2D (3,8)-connected framework with a {3·42}2{34·46·56·68·73·8} topology comprising [Cd3(COO)6] SBUs. Both MOFs have been used as photocatalysts for the photodegradation of aromatic dyes, and experiments demonstrate that 1 and 2 exhibit 95.5% and 86.2% photodegradation of methyl violet (MV), respectively, in a time span of 100 min. Moreover, both MOFs offer better photodegradation of MV than other model dyes such as rhodamine B, methyl blue and methyl orange. Additionally, the effects of catalyst amount and dye concentration on dye degradation have been explored. Further, trapping experiments indicate that ˙OH and ˙O2− are the active species responsible for the degradation of MV in the presence of 1. Both MOFs could be recycled and used repeatedly as photocatalysts for the degradation of MV, which showcases their highly stable nature. Density of states plots and Hirshfeld surface analyses have been performed to address the plausible photocatalytic mechanistic pathways. [ABSTRACT FROM AUTHOR]

A new 3D luminescence metal–organic framework with open channels was constructed by the assembling of the zwitterionic H 3 L Cl ligand and Zn(II) ions under solvothermal conditions. The compound exhibits relatively high luminescence selective sensing for Fe 3 + ions with surprisingly excellent recyclability, making it a promising candidate for sensing metal ions in practical. [ABSTRACT FROM AUTHOR]

A new lanthanide metal–organic framework was constructed using a tripodal flexible zwitterion ligand (H3LBr3) which takes a chair-shaped configuration. The luminescence of the compound displays highly selective sensing of the Fe3+ ion and nitrobenzene. [ABSTRACT FROM AUTHOR]

Abstract: A new hybrid compound based on porous metal–organic frameworks and polyoxometalates H4[(Cu4Cl)3(BTC)8]2[SiW12O40]·(C4H12N)6·3H2O (NENU-15, BTC=1, 3, 5-benzenetricarboxylate) has been hydrothermally synthesized and its crystal structure, stability and porosity have been characterized. The experimental results showed that the introduction of polyoxometalates improved the integral stability of the compound. In addition, NENU-15 was employed in NO removal for the first time. By virtue of the synergistic effect between host frameworks and guest polyoxometalates, it not only displayed good adsorption behavior for NO, but also exhibited superior activity in NO decomposition. [Copyright &y& Elsevier]

A stable Co(II)-based metal–organic framework (MOF) was constructed by applying a dual ligand strategy. The ultra-stable Co(II) MOF, [Co(H3tpb)(Hbtc)]n (1), was obtained by hydrothermal reaction of a novel trimer pyrazole ligand H3tpb and a classic carboxylic ligand H3btc (H3tpb = 1,3,5-tris (pyrazolyl) benzene, H3btc = 1,3,5-benzoic acid). In addition, complex 1 shows photocatalytic activity for the degradation of the dyes methylene blue (MB) and methyl orange (MO) under UV light. About 83.8% MB and 75.3% MO could be removed within 150 min. Serial experiments were performed to evaluate the biological activity of this compound in neonatal sepsis and explore its related mechanism. The results of the ELISA showed that the compound could reduce the releasing of the inflammatory cytokines in a dose-dependent manner. Besides, the compound could also reduce the relative expression levels of the gram-positive bacterial virulence. Simulations based on the molecular docking found that the complex could form multiple hydrogen bonds with several residues in the domain pocket. [ABSTRACT FROM AUTHOR]

• The porous dawsonite is synthesized by the digestion of MOFs precursor. • Dawsonite shows a mesoporous structure with a large specific surface area. • The maximum adsorption capacity can reach 228.25 mg/g at 303 K. • OH− and CO 3 2− play an important role for Cu(II) removal. Mesoporous dawsonite was successfully synthesized using metal-organic frameworks (MOFs) as the template and precursor by direct digestion of NH 2 -MIL-53(Al) with the help of bismuththiol and Na 2 CO 3 and was applied to eliminate Cu(II) from wastewater. The mesoporous dawsonite was characterized by ICP, SEM-EDS, TEM, AFM, FTIR, XRD, XPS, EA, TGA, zeta potential and nitrogen adsorption-desorption isotherms. The influence factors on the adsorption were discussed, including initial Cu(II) concentration, temperature, solution pH, contact time, and co-cation. The results showed that the adsorption isotherm and adsorption kinetics of Cu(II) onto dawsonite obeyed Langmuir and pseudo-2nd-order kinetic equations, respectively. Thermodynamic analysis revealed adsorption of Cu(II) onto dawsonite was spontaneous and thermodynamically favorable. The efficient elimination of Cu(II) was ascribed to cation exchange and the inner-sphere complexation between Cu(II) and surface hydroxyl or carbonate groups of dawsonite. The high adsorption performance and reusability suggest the dawsonite prepared here is an efficient adsorbent to eliminate Cu(II) from wastewater. [ABSTRACT FROM AUTHOR]

A metal-organic framework (MOF) with sulfonic acid group (denoted as MIL-101-SO 3 H) was directly synthesized without post-synthesis method and applied to remove methylene blue (MB) and malachite green (MG) from aqueous solution. Characterizations of MIL-101-SO 3 H were achieved by XRD, TEM, XPS, nitrogen adsorption-desorption analysis and elemental analysis. MIL-101-SO 3 H mainly possessed mesopore, high surface area, big pore volume and anionic group which are benefit for the adsorption of cationic dye. The adsorption isotherm, thermodynamic parameters and kinetics characteristic of dye adsorption onto MIL-101-SO 3 H were investigated. The experimental isotherm data were analyzed using Langmuir isotherm equation and the results indicated the Langmuir isotherm was suitable to describe the adsorption behaviors. Thermodynamic parameters calculated by the Gibbs free energy function, confirm the adsorption process was spontaneous, endothermic and entropy-driven. The pseudo-second-order and intraparticle diffusion, were employed to obviously describe the adsorption mechanism. The dye adsorption capacities of MIL-101-SO 3 H were found to increase as the initial pH values in the experimental ranges. These results suggested the π-π interactions between the aromatic rings of MB and MG with MIL-101-SO 3 H may be mainly interactions in low pH values and electrostatic interactions can gradually increase with increasing initial pH values. [ABSTRACT FROM AUTHOR]

[Display omitted] Coordination chemistry has always been vital to explore the material prominence of metal–organic systems. The metal–organic chemistry plays a fundamental role in decisive structural features, which are accountable for tuning the properties of materials. Tumour therapy has become an important research field of medical treatment in the world. Metal-organic frameworks (MOFs) have attracted extensive interest in medical science research due to their large effective surface area, clear pore network, and critical catalytic performance. Compared with traditional MOF materials, MOF materials with core–shell structures have a higher loading rate and better stability, which can overcome a single function. They have been successfully used in tumour medical research and have excellent prospects for diagnosing and treating various tumours. The current review article thoroughly describes the various synthetic approaches for engineering core–shell MOF materials, the structural types, and the potential functional applications. We also discussed core–shell MOF materials for the various treatment of tumours, such as tumour chemotherapy, tumour phototherapy and tumour microenvironment anti-hypoxia therapy. In this paper, the synthesized procedures of core–shell MOFs and their applications for tumour treatment have been discussed, and their future research has prospected. The current improved strategies, challenges, and prospects are also presented because of the metal–organic chemistry governing the structural modification of core–shell MOFs for tumour therapy applications. Therefore, the present review article opens a new door for medicinal chemists to tune the structural features of the core–shell MOF materials to modulate tumour therapy with simple, low-cost materials for better human lives. [ABSTRACT FROM AUTHOR]

Abstract: Reactions of different metal salts with 3-pyridin-4-yl-benzoic acid (3,4-Hpybz) under ambient condition afford a series of 3-D metal-organic frameworks with two new types of (3,6)-connected net topologies. In the isomorphic complexes [M 2(μ-H2O)(3,4-pybz)4] n (M II=MnII for 1, ZnII for 2, or CdII for 3), the octahedral metal nodes are extended by the 3-connected pybz tectons to constitute 3-D arrays with the Schläfli symbol of (3.4.5)(32.44.55.62.72), whereas [Pb(3,4-pybz)2] n (4) shows a completely different 3-D (42.6)2(44.62.89) framework, which represents a subnet of the (4,8)-connected fluorite lattice. [Copyright &y& Elsevier]