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1 The 2D and 3D Fobs electron density maps for the BCDD molecules observed by the previously reported (a, b) and newly collected SCXRD data (c, d) of BCDD@BUT-17, respectively. 4, the molar ratio of ligand to BCDD in BCDD@BUT-17 was estimated to be 1/0.16, consistent with that obtain from the single-crystal structure (1/0.15), further validating the rationality of the obtained single-crystal structures of BCDD@BUT-17. The sensing mechanism was ascribed to the formation of the nonfluorescent ground-state complexes between the PCDD molecules and the fluorophore of BUT-17, which was supported by the single-crystal structure of BCDD-loaded BUT-17 (BCDD@BUT-17) and adsorption experiments. [Extracted from the article]

The structure of the framework with the absorbed guest molecules (2,3-dichlorodibenzo-p-dioxin, BCDD) has been determined via single-crystal X-ray diffraction (XRD). Therefore, the XRD data do not support the claim that BCDD molecules have been adsorbed in the MOF. To make proper use of XRD, one should remember that the framework atoms contribute much more to the Bragg diffraction intensities than the disordered guest molecules. The map of the total electron density in the plane of BCDD (Fourier transform of F SB obs sb ) reveals no maximum corresponding to atoms of the molecule included in the model (Fig. [Extracted from the article]

Graphical abstract Highlights • A highly porous Zr(MOF) modified with HPW as an effective adsorbent for the BT removal. • High maximum adsorption capacity (290 mg.g−1) for BT on HPW(1.5)/Zr(BTC) adsorbent. • DFT calculations predicted that BT binds stronger on HPW/Zr(BTC) than on Zr(BTC). • The adsorbents were used for at least five runs maintaining much of active adsorption sites. Abstract Reduction of sulfur-containing compounds from fossil fuel is vital. This work reports on the adsorptive removal of benzothiophene (BT) from liquid fuel using a highly porous metal-organic framework based on a bicomponent zirconium(IV) benzene-tricarboxylate Zr(BTC), and its post-synthetically modified hybrid form with dodeca-tungstophosphoric acid (HPW/Zr(BTC). The HPW loading for the high-performing hybrid adsorbents was 0.5–2.0 wt/wt of W/Zr. Temperature and concentration dependent BT adsorption data were in good agreement with the non-linear Langmuir model combined with a van't Hoff description of the heat of adsorption. The maximum predicted adsorption capacities were estimated to be 290 and 238 mg.g−1 for HPW(1.5)/Zr(BTC) and Zr(BTC) comparable to the contemporary reported adsorbents. The adsorption kinetics followed a pseudo-second order model, which was related to the low concentration of BT used for these studies. Although the highly porous Zr(BTC) had good adsorptive sites, its adsorption capacity was enhanced by incorporation of HPW, this was attributed to availability of added acid sites for adherence of basic BT. The adsorption findings were further corroborated with DFT calculations, which showed favorable BT adsorption with calculated binding energies of −140.2 and −47.3 kJ.mol−1 for HPW(1.5)/Zr(BTC) and Zr(BTC), respectively. Much of adsorption sites were retained after regeneration of adsorbents. [ABSTRACT FROM AUTHOR]

Herein we report a facile bottom-up strategy to prepare highly dispersed supported Co 3 O 4 on N-doped Porous Carbon (NPC). Specifically, ZIF-67 (ZIF = Zeolitic Imidazolate Frameworks) microcrystals firstly grow on benzoic acid modified covalent organic framework (BFC), resulting in ZIF-67/COF composite. Subsequently, highly dispersed Co 3 O 4 /NPC was obtained via the calcination of ZIF-67/COF. Interestingly, high dispersion of supported Co 3 O 4 is dominated by homogeneous distribution of benzoic acid auchoring on nanoporous COF. More notably, largely triggered by the porosity and confining effect of COF, the resultant Co 3 O 4 /NPC features highly active crystal plane and a large specific surface area of 228.0 m 2 /g. Furthermore, the oxygen evolution reaction (OER) measurement results demonstrated that highly dispersed Co 3 O 4 /NPC features good catalytic activity (330 mV overpotential at 10 mA.cm −2 , 79 mV.dec −1 Tafel slope and mass activity of 130 A.g −1 at overpotential of 400 mV) and durable stability, superior to currently available counterparts. Moreover, Li-ion battery (LIB) tests also showed high reversible capacity (785 mA.h.g −1 at 500 mA.g −1 ) as well as excellent cycling stability and rate performance. Furthermore, Density functional theory (DFT) calculation results demonstrated that these superior OER properties can be attributed to the geometrical and electronic effects of Co 3 O 4 /NPC on activation and adsorption/desorption of reaction species. [ABSTRACT FROM AUTHOR]

The reaction of silver(I) nitrate with the mono-substituted pyrazine carboxamide ligand, N-(pyridin-2-ylmethyl)pyrazine-2-carboxamide (L), led to the formation of the title compound with a metal-organic framework (MOF) structure, [Ag(Cn11H10N4O)(NO3)]n, poly[μ-nitrato-[μ-N-(pyridin-2-ylmethyl-κN)pyrazine-2-carboxamide-κN4]silver(I)]. The silver(I) atom is coordinated by a pyrazine N atom, a pyridine N atom, and two O atoms of two symmetryrelated nitrate anions. It has a fourfold N2O2 coordination sphere, which can be described as distorted trigonal-pyramidal. The ligands are bridged by the silver atoms forming -Ag-L-Ag-L- zigzag chains along the a-axis direction. The chains are arranged in pairs related by a twofold screw axis. They are linked via the nitrate anions, which bridge the silver(I) atoms in a μ2 fashion, forming the MOF structure. Within the framework there are N--H...O and C--H...O hydrogen bonds present. [ABSTRACT FROM AUTHOR]

New metal-organic frameworks (MOFs) based on zinc and cadmium ions, terephthalic acid, and flexible ligands 1,5-bis(imidazol-1-yl)pentane or 1,6-bis(imidazol-1-yl)hexane were prepared and characterized by X-ray diffraction, thermorgavimetric analysis and IR spectroscopy. The imidazolyl ligands were prepared by a new robust procedure involving the reaction between imidazole and 1,5-dibromopentane or 1,6-dibromohexane in a superbasic medium (KOH in DMSO). MOFs based on 1,5-bis(imidazol-1-yl)pentane had diamond topology (dia) and are triply interpenetrated. Ligands with longer spacer 1,6-bis(imidazol-1-yl)hexane, terephthalate ions and zinc(II) ions formed five-fold interpenetrated metal-organic framework also with dia topology, while cadmium(II) ions with the same ligands formed eight-connected uninodal net with a very rare self-penetrated topological type ilc and a point symbol 424.5.63. The influence of the chemical composition of MOFs on their photoluminescent properties is investigated and discussed in detail. [ABSTRACT FROM AUTHOR]

The processing of an originally non-porous 1D coordination polymer as monolithic gel, xerogel and aerogel is reported as an alternative method to obtain novel metal-organic porous materials, conceptually different to conventional crystalline porous coordination polymer (PCPs) or metal-organic frameworks (MOFs). Although the work herein reported is focused upon a particular kind of coordination polymer ([M(μ-ox)(4-apy)2]n, M: Co(II), Ni(II)), the results are of interest in the field of porous materials and of MOFs, as the employed synthetic approach implies that any coordination polymer could be processable as a mesoporous material. The polymerization conditions were fixed to obtain stiff gels at the synthesis stage. Gels were dried at ambient pressure and at supercritical conditions to render well shaped monolithic xerogels and aerogels, respectively. The monolithic shape of the synthesis product is another remarkable result, as it does not require a post-processing or the use of additives or binders. The aerogels of the 1D coordination polymers are featured by exhibiting high pore volumes and diameters ranging in the mesoporous/macroporous regions which endow to these materials the ability to deal with large-sized molecules. The aerogel monoliths present markedly low densities (0.082-0.311 g ⋅ cm-3), an aspect of interest for applications that persecute light materials. [ABSTRACT FROM AUTHOR]

C52H40Co2N8O14, triclinic, P1¯ (no. 2), a = 11.423(5) Å, b = 13.051(6) Å, c = 17.776(8) Å, α = 74.185(5)°, β = 86.110(6)°, γ = 70.758(6)°, V = 2407(2) Å3, Z = 2, Rgt(F) = 0.0933, wRref(F2) = 0.1817, T = 296 K. [ABSTRACT FROM AUTHOR]

C16H28FeN2O11S2, monoclinic, Pc (no. 7), a = 14.6849(5) Å, b = 7.7856(2) Å, c = 20.1174(7) Å, β = 98.020(2)°, V = 2277.6 Å3, Z = 4, Rgt(F) = 0.0346, wRref(F2) = 0.0675, T = 120 K. [ABSTRACT FROM AUTHOR]

C16H28FeN2O11S2, monoclinic, Pc (no. 7), a = 14.6849(5) Å, b = 7.7856(2) Å, c = 20.1174(7) Å, β = 98.020(2)°, V = 2277.6 Å3, Z = 4, Rgt(F) = 0.0346, wRref(F2) = 0.0675, T = 120 K. [ABSTRACT FROM AUTHOR]

C30H42CdF12N12-P2, trigonal, P3 (no. 143), a = 13.318(2) Å, c = 13.278(2) Å, V = 2039.4 Å3, Z = 2, Rgt(F) = 0.0353, wRref(F2) = 0.0954, T = 193 K. [ABSTRACT FROM AUTHOR]

C54H60Cd2Cl4N10O3, monoclinic, P21/c (no. 14), a = 9.552(2) Å, b = 26.647(5) Å, c = 11.094(2) Å, β = 98.23(3)°, V = 2794.7 Å3, Z = 2, Rgt(F) = 0.0485, wRref(F2) = 0.0968, T = 293 K. [ABSTRACT FROM AUTHOR]

C38H30Cl2N4O4Zn, monoclinic, P21/c (no. 14), a = 11.5694(8) Å, b = 14.143(1) Å, c = 21.969(2) Å, β = 100.856(2)°, V = 3530.5 Å3, Z = 4, Rgt(F) = 0.0499, wRref(F2) = 0.1282, T = 296 K. [ABSTRACT FROM AUTHOR]

C30H42CdF12N12-P2, trigonal, P3 (no. 143), a = 13.318(2) Å, c = 13.278(2) Å, V = 2039.4 Å3, Z = 2, Rgt(F) = 0.0353, wRref(F2) = 0.0954, T = 193 K. [ABSTRACT FROM AUTHOR]

In order to assess how metal doping affects the luminescence and magnetic properties of anionic Metal-Organic Frameworks (MOFs), seven single-metal doped MOFs {M-Zn-BTC}{Me2NH2+} (M = Co, Cu, Ni, Mn, Ca, Mg, Cd) and three dual-metal doped MOFs {Zn-M1-M2-BTC}{Me2NH2+} (M1 = Co, Cu; M2 = Ni, Co) were synthesized. Trace amounts of different metals were doped via addition of another metal salt during the synthetic process. All compounds retained the same crystal structure as that of the parent {Zn-BTC}{Me2NH2+} MOF, which was supported by single crystal and powder X-ray diffraction studies. Thermal Gravimetric Analysis (TGA) of these compounds also revealed that all MOFs had similar stability up to ~450 °C. Solid state photoluminescent studies indicated that {Zn-Mn-BTC}{Me2NH2+}, {Zn-Cd-BTC}{Me2NH2+}, and {Zn-Ca-BTC}{Me2NH2+} had a significant red shifting effect compared to the original {Zn-BTC}{Me2NH2+} MOF. Applications of this doping method to other MOF systems can provide an efficient way to tune the luminescence of such systems, and to obtain a desired wavelength for several applications such as sensors and white light LED materials. Because Zn, Co, Cu, Ni, Mg have magnetic properties, the effect of the doping metal atom on the magnetism of the {Zn-BTC}{Me2NH2+} networks was also studied. To characterize the magnetic behavior of the synthesized MOFs, we conducted low-temperature (10 K) saturation remanence experiments in a 3 Tesla applied field, with the principal goal of identifying the domain state of the synthesized materials (Zn, Zn-Co, Zn-Cu-Co, Zn-Cu-Ni, Zn-Mg, Zn-Mn, Zn-Ni-Co, Zn-Ni). During room/low temperature saturation magnetization experiments, Zn, Zn-Co, Zn-Cu-Co, and Zn-Cu-Ni systems yielded data indicative of superparamagnetic behavior, yet during zero field and field cooled experiments Zn-Co showed a slight paramagnetic effect, Zn showed no temperature dependence on warming and Zn-Cu-Co and Zn-Cu-Ni demonstrated only a slight temperature dependence on warming. These behaviors are consistent with ferromagnetic ordering. Zero field and field cooled experiments indicate that Zn-Mg and Zn-Ni have a ferromagnetic ordering and Zn-Mn and Zn-Ni-Co show paramagnetic ordering behavior. [ABSTRACT FROM AUTHOR]