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In the current study, thin-film nanocomposite membranes (TFN-Mx) based on a zwitterion-functionalized metal–organic framework (MOF) have been developed for the forward osmosis (FO) salt-water separation process. The active polyamide layer was formed through the interfacial polymerization of the m-phenylenediamine aqueous phase (with or without the presence of MIL-125-NH-CC-Cys) and the trimesoyl chloride organic phase. In comparison with the results from the surface of the unmodified membrane, a nanofiller-incorporated TFN-M0.10 membrane represents a smoother and more wettable surface that collaborates synergically to enhance the membrane antifouling ability. Among the examined membranes, the TFN-M0.10 membrane shows the highest water flux of 39.6 LMH under the AL-DS (active layer facing draw solution) mode in 1 M NaCl as a draw solution. This performance of the optimal membrane was carried out without any increase in the specific salt flux (Js/Jw). In the AL-FS (active layer facing feed solution) mode, the TFN-M0.10 membrane improved the selectivity by almost 30% compared to the nanofiller-free membrane. Moreover, Cu(II) ions' removal performance of the optimal membrane was eventually investigated. Owing to the molecular sieving character of the applied MOF and the presence of diverse functional groups on the inserted nanofillers, the modified membranes demonstrate a higher Cu(II) rejection value than the unmodified one. This work presents new insights into the development of TFN-FO membranes and the feasibility of using zwitterion-functionalized MOFs as a modifier. [ABSTRACT FROM AUTHOR]

Cu2+ ions immobilized on a novel magnetic chitosan-based catalytic system were prepared in combination with laponite RD. The CuII–magnetic chitosan/laponite RD (Cu–mCSLap) nanocomposite was characterized via X-ray diffraction, energy dispersive X-ray, scanning electron microscopy, and transmission electron microscopy. Further, the catalytic activity of this well-defined material was investigated in three-component CuAAC reactions to obtain 1,4-disubstituted-1,2,3-triazoles in good to excellent yields from an organic halide, sodium azide, and an alkyne using air-in-water as a green solvent. [ABSTRACT FROM AUTHOR]

Four Pb(ii) complexes of (iso)nicotinohydrazide-based ligands and different anionic coligands (azide, nitrate, acetate and iodide) have been synthesized and characterized by structural, analytical and spectroscopic methods. The mono-deprotonated or neutral forms of the ligands coordinate in a tridentate fashion via two nitrogen and one oxygen donor atoms to the Pb. Single-crystal X-ray crystallography showed that the molecular complexes can aggregate into larger entities depending upon the anion coordinated to the metal centre. In all four complexes the lead center is hemidirectionally coordinated and, consequently, it is sterically ideal for establishing tetrel bonding interactions. In the crystal structures of all complexes, the lead atoms participate in short contacts with nitrogen atoms. These contacts are shorter than the sums of the van der Waals radii and larger than the sums of the covalent radii. The tetrel bonding interactions interconnect the covalently bonded units (monomers or dimers) into supramolecular assemblies (chains and 3D structures). We have analysed the interesting supramolecular assemblies observed in the solid state of all four complexes by means of DFT calculations. [ABSTRACT FROM AUTHOR]

We report a simple methodology for the stabilization of Cu2O nanoparticles of size 10–30 nm on the polar pore surface of the polyoxomolybdate (NH4)12[Mo36(NO)4O108(H2O)16] ({Mo36}). For the first time, a Cu2O@{Mo36} composite has been utilized as a recyclable catalyst for the Huisgen 1,3-dipolar cycloaddition reaction of terminal alkynes, aryl/alkyl halides and NaN3 for the synthesis of 1,2,3-triazoles. [ABSTRACT FROM AUTHOR]

Herein new findings on the alcohol-oxidizing activity of a mononuclear manganese(ii) complex are reported. We propose that nano-sized Mn oxides are true catalysts for the oxidation of some alcohols to aldehydes in the presence of Oxone (2KHSO5·KHSO4·K2SO4) as an oxidant. [ABSTRACT FROM AUTHOR]

Herein we report on the synthesis and characterization of a hexanuclear [MnII6] wheel-like assembly with naphthalene-1,8-dicarboxylate and 1,10-phenanthroline as ligands. Overall antiferromagnetic behavior of the magnetic properties is observed. The complex acts as a catalyst toward organic sulfide oxidation in the presence of H2O2 with good selectivity (98–100%). [ABSTRACT FROM AUTHOR]

V/TiO2 nanoparticles were synthesized by a one-pot solution combustion method using ammonium metavanadate and titanyl nitrate as a source of vanadium and titanium, respectively. Atomic absorption spectroscopy (AAS), FT-IR, X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to characterize the physicochemical properties of this compound. This compound shows efficient catalytic reactivity for epoxidation of olefins and oxidation of alcohols in the presence of H2O2 as an oxidant. [ABSTRACT FROM AUTHOR]

MnOx/WO3 nanoparticles were synthesized by an impregnation method and the physicochemical properties of compounds were characterized by atomic absorption spectroscopy (AAS), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The catalytic degradation of an organic dye, methylene blue, in the presence of nano-MnOx supported on WO3 as a catalyst and hydrogen peroxide, H2O2, as the oxidant has been studied at room temperature in water. The effects of oxidant amount, catalyst composition and an OH-radical scavenging agent on the degree of decomposition of MB dye were also studied. [ABSTRACT FROM AUTHOR]

Four Pb(ii) complexes of (iso)nicotinohydrazide-based ligands and different anionic coligands (azide, nitrate, acetate and iodide) have been synthesized and characterized by structural, analytical and spectroscopic methods. The mono-deprotonated or neutral forms of the ligands coordinate in a tridentate fashion via two nitrogen and one oxygen donor atoms to the Pb. Single-crystal X-ray crystallography showed that the molecular complexes can aggregate into larger entities depending upon the anion coordinated to the metal centre. In all four complexes the lead center is hemidirectionally coordinated and, consequently, it is sterically ideal for establishing tetrel bonding interactions. In the crystal structures of all complexes, the lead atoms participate in short contacts with nitrogen atoms. These contacts are shorter than the sums of the van der Waals radii and larger than the sums of the covalent radii. The tetrel bonding interactions interconnect the covalently bonded units (monomers or dimers) into supramolecular assemblies (chains and 3D structures). We have analysed the interesting supramolecular assemblies observed in the solid state of all four complexes by means of DFT calculations.

Herein new findings on the alcohol-oxidizing activity of a mononuclear manganese(II) complex are reported. We propose that nano-sized Mn oxides are true catalysts for the oxidation of some alcohols to aldehydes in the presence of Oxone (2KHSO5·KHSO4·K2SO4) as an oxidant.

Nano-sized particles of manganese oxides have been prepared by a very simple and cheap process using a decomposing aqueous solution of manganese nitrate at 100 °C. Scanning electron microscopy, transmission electron microscopy and X-ray diffraction spectrometry have been used to characterize the phase and the morphology of the manganese oxide. The nano-sized manganese oxide shows efficient catalytic activity toward water oxidation and the epoxidation of olefins in the presence of cerium(IV) ammonium nitrate and hydrogen peroxide, respectively.