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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]

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]

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]

• 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]

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]