Search

The synthesis of nanoclusters from simple structural units is usually a challenging process because of the complexity and unpredictability of the self-assembly process of these types of compounds. Herein, two new neutral 19-nuclearity silver nanoclusters based on alkynyl ligands with the formulas [(CrO

Advancement of the synthesis and control of the self-assembly process of new high-nucleus silver clusters with desired structures is important for both the material sciences and the many applications. Herein, three new silver clusters, 20-, 22-, and 8-nucleus, based on alkynyl ligands were constructed and their structures were confirmed by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analyses, and Fourier-transform infrared spectroscopy (FT-IR). For the first time, the trivalent tetrahedron anion of AsO

Five new cadmium(II) coordination polymers [Cd(HPBO)(2,2′-bipy)]n (C1), (H3PBO = 4,4′-(hydroxyphosphoryl)dibenzoic acid, 2,2′-bipy = 2,2′-bipyridine), [Cd(HPBO)(phen)]n (C2), (phen = 1,10-phenanthroline), [Cd(HPBO)(4,4′-bipy)0.5]n (C3) (4,4′-bipy = 4,4′-bipyridine), [Cd(HPBO)(dpe)0.5]n (C4), (dpe = 1,2-di(pyridin-4-yl)ethene), [Cd2(HPBO)2(dpp)]n (C5), (dpp = 1,3-di(pyridin-4-yl)propane) were synthesized and characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction. The thermal stabilities and luminescence properties of compounds C1–C5 were investigated. The N-donor ligands influence the coordination mods of the Cd(II) centers and dimensionality of the structures and H3PBO accept either bridging and chelating modes. C2 exhibits a 3-connected 2D network of a hcb topology with a point symbol of (63). C3 and C4 show the same unprecedented (4, 10)-connected 3D network with a point symbol of (412·511·618·73·8)(46)2. C5 presents a (4, 10)-connected 3D network of a deh1 topology with a point symbol of (3·45)2(34·412·510·614·73·82).

The binding of ruthenium(II) complexes of formulation [(η6-p-cymene)RuCl(L1)]PF6 (1) and [(η6-C6H6)RuCl(L1)]PF6 (2), L1= (E)-4-nitro-N-(quinolin-2-ylmethylene)aniline, to calf thymus–DNA (CT-DNA) were investigated via techniques include electronic absorption spectra, fluorescence and redox behavior (cyclic voltammetry) and the results of the analysis of complexes 1 and 2 are compared with the results of complexes 3 and 4, [(η6-p-cymene)RuCl(L1)]PF6 (3) and [(η6-C6H6)RuCl(L2)]PF6 (4), L2=(E)-N-((6-bromopyridin-2-yl)methylene)-4-nitroaniline. Single crystals of the complexes were separated by the slow evaporation method and they were characterized by elemental analysis, 1H NMR and 13C NMR spectroscopy and the thermal studies of them were studied by thermal gravimetric (TG) and differential scanning calorimetry (DSC). Also, it has been shown that the complexes are photosensitive molecules. RuO2 nanoparticles were prepared by calcination of the complexes and it was investigated the influence of the treating by ultrasound on the characteristics of the samples before calcination.

Atomically precise silver nanoclusters (Ag-NCs) are known as a hot research area owing to their brilliant features and they have attracted an immense amount of research attention over the last year. There is a lack of sufficient understanding about the Ag-NC synthesis mechanisms that result in optimal silver nanoclusters with an appropriate size, shape, and morphology. In addition, the coexisting flexible coordination of silver ions, the argentophilic interactions, and coordination bonds result in a high level of sophistication in the self-assembly process. Furthermore, the expansion of clusters by the organic ligand to form a high dimensional structure could be very interesting and useful for novel applications in particular. In this study, a novel two-dimensional 14-nucleus silver poly-cluster was designed and synthesized by the combination of two synthetic methods. The high nucleus silver cluster units are connected together via tetradecafluoroazelaic acid (CF2) and this leads to the high stability of the polymer. This highly stable conductive poly-cluster, with bridging groups of difluoromethylene, displays a high energy density (372 F g−1 at 4.5 A g−1), excellent cycling stability, and great capacity. This nanocluster shows a high power density and long cycle life over 6000 cycles (95%) and can also tolerate a wide range of scan rates (5 mV s−1 to 1 V s−1), meaning it could act as a green energy source.

A high-nucleus silver nanopolycluster as a new type of silver-based polymer supercapacitor (SSc) by a simple and single-step synthesis process was designed and synthesized. The structural, optical, and electrochemical properties of SSc-2 were determined. This highly stable conductive 3D nanopolycluster shows great cycling stability, large capacity, and high energy density without any modification or doping process and so acts as an excellent SSc (412 F g-1 at 1.5 A g-1). In addition, there was a stable cycling performance (94% capacitance) following 7000 cycles at 3 A g-1 current density. The presence of fluorinated groups, 3D expansion of high-nucleus metallic clusters, and porosity are the advantages of SSc-2 that lead to stability, conductivity, and high capacity, respectively. These results lead to the development of a novel kind of SSc by overcoming the low conductivity and limited capacity challenges without any modification.

The first silver nanocluster with an octahedral template of TeO66– was synthesized as a neutral 36-nucleus nanocluster, and its structure was demonstrated using single-crystal X-ray diffraction, Fo...

New 2D lead(II) coordination polymers, Pb(4-bpdh)(CH3COO)(NO3)]n (1) and [Pb(4-bpdh)(ClO4)(NO3)]n (2), 4-bpdh ​= ​2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene, were prepared and characterized by single-crystal X-ray diffraction. Compound 3 with formula [Pb(4-bpdh)(NO3)2(H2O)]n (3) was obtained by solid state mechanochemical reaction of the compounds 1 and 2 via anion-exchange process. These conversions are reversible and the grinding of compound 3 with CH3COO¯ and ClO4¯ ions led to the formation of the compounds 1 and 2, respectively. Thermal decomposition of the compounds 1–3 results in the formation of different metallic composites. The composites were characterized by X-ray powder diffraction (XRD) and size and morphology of them were investigated by scanning electron microscopy (SEM).

Two novel Ru(II) complexes [(η6-p-cymene)RuCl(L2)]PF6 (R2) and [(η6-C6H6)RuCl(L2)]PF6 (R4), with ligand (E)-N-((6-bromopyridin-2-yl)methylene)-4-(methylthio)aniline (L2), were synthesized and characterized by elemental analysis, 1H NMR, 13C NMR and IR spectroscopy. Based on X-ray crystallography studies, complexes R2 and R4 have coordination environments with formulated (η6-p-cymene)Ru(N2Cl) and (η6-C6H6)Ru(N2Cl), respectively. The thermal stabilities of compounds R2 and R4 were studied by thermal gravimetric (TG) and differential scanning calorimetry (DSC). Thermal decomposition of these complexes was at 280°C and 260°C under air atmosphere respectively. The interaction of these complexes with calf thymus DNA (CT-DNA) was explored through electronic absorption spectra, fluorescence and redox behavior studies. The results showed that the complexes bind to CT-DNA with electrostatic interactions. Nanoparticles of RuO2 were prepared by calcination of R2 and R4. Also the role of the ultrasound waves on the characteristics of the RuO2 nanoparticles was studied. The nanoparticles were characterized by IR spectroscopy and X-ray diffraction (XRD). Also size and morphology of nanoparticles were studied by scanning electron microscopy (SEM).

Two novel Ru(II) complexes [(η6-p-cymene)RuCl(L1)]PF6 (R1) and [(η6-C6H6)RuCl(L1)]PF6 (R3) with ligand (E)-4-(methylthio)-N-((quinolin-2-yl)methylene)benzenamine (L1), were synthesized and investigated using elemental analysis, IR, 1H NMR, 13C NMR spectroscopy and X-ray crystallography. Complexes R1 and R3 have coordination environments with formulated (η6-p-cymene)Ru(N2Cl) and (η6-C6H6)Ru(N2Cl) respectively. The thermal stabilities of compounds R1 and R3 were studied by thermal gravimetric (TG) and differential scanning calorimetry (DSC). The binding of the complexes R1 and R3 to calf thymus DNA (CT DNA) was investigated by using electronic absorption spectra, fluorescence and redox behavior studies. Such experimental data showed that there are interactions between complexes and CT-DNA and the nature of this binding is electrostatic interaction type. Calcination of ultrasonic treated R1 and R3 results in the formation of nanoparticles of RuO2. The nanoparticles were characterized by IR spectroscopy and X-ray diffraction (XRD). Also size and morphology of nanoparticles were investigated by scanning electron microscopy (SEM).

A new mercury(II) coordination polymer, [Hg(4-bpmo)I2]n (1), (4-bpmo=N,N'-bis(pyridin-4-ylmethyl)oxalamide), was synthesized, by branched tube method, and structurally characterized by single-crystal X-ray diffraction. Compound 1 is a polymer with a distorted tetrahedral HgN2I2 coordination environment. The thermal stability of 1 was studied by thermal gravimetric (TG) and differential thermal (DTA) analyses. Also 1 was prepared by a sonochemical process at ambient temperature. Reaction time and concentration of initial reagents effects on the size and morphology were studied. Nanoparticles of 1, was synthesized easily by a mechanical method (neat grinding). The resulting structures were characterized by scanning electron microscopy (SEM), IR spectroscopy and X-ray powder diffraction (XRD).

A 3D, porous Zn(II)-based metal-organic framework {[Zn2(oba)2(4-bpmn)]·(DMF)1.5}n (TMU-21), (4-bpmn=N,N'-Bis-pyridin-4-ylmethylene-naphtalene-1,5-diamine, H2oba=4,4'-oxybis(benzoic acid)) with nano-rods morphology under ultrasonic irradiation at ambient temperature and atmospheric pressure was prepared and characterized by scanning electron microscopy. Sonication time and concentration of initial reagents effects on the size and morphology of nano-structured MOFs were studied. Also {[Zn2(oba)2(4-bpmn)] (TMU-21) and {[Zn2(oba)2(4-bpmb)] (TMU-6), 4-bpmb=N,N'-(1,4-phenylene)bis(1-(pyridin-4-yl)methanimine) were easily prepared by mechanochemical synthesis. Nanostructures of Zinc(II) oxide were obtained by calcination of these compounds and their de-solvated analogue as activated MOFs, at 550°C under air atmosphere. As a result of that, different Nanostructures of Zinc(II) oxide were obtained. The ZnO nanoparticles were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and FT-IR spectroscopy.

In order to study the charge effect on the formation of an anion-templated silver cluster, a trivalent tetrahedral anion was incorporated into the silver assembly. A 26-nuclear silver cluster was prepared, and its structure was confirmed by single-crystal X-ray diffraction. Also, the resulting structure was characterized by powder X-ray diffraction data. Its light absorption and photoluminescent properties were studied by solid-state UV diffuse-reflectance and fluorescence spectroscopy. Compared with the other reported silver clusters with tetrahedral anion templates, the more negative VO43- anion led to the formation of a bigger silver cluster. Also, the supramolecular motif O-H(CH3OH)···O(trifluoroacetate) was confirmed on the cluster surface for the first time.

Two new silver clusters, [Ag6(PhC C)2(bpy)4(NO3)4] (1), bpy = 2,2′-bipyridine, Ag8(Phen)4(NEA)8(CH3CN)2 (2), NEA = naphthalene acetic acid, were synthesized with assistance of ultrasonic irradiation and their unique structure investigated by single-crystal X-ray diffraction, Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction analysis (PXRD) and Ultraviolet–visible spectrum (UV–Vis). Thermal stability of the clusters were studied through thermogravimetric analysis (TGA). The photoluminescence analysis of 2 was also carried out. Clusters 1 and 2 show the absorption bands at λmax in the range 200–380 nm and 310 nm, respectively. The band gap widths for clusters are 3.05 eV and 3.20 eV. The Ag…Ag contact range in the cluster 1 is 2.7211(4) A–3.1102(3) A and for the cluster 2 is 2.867–3.047 A.

A novel binuclear Cu(II) complex based on ferrocene dicarboxylate was synthesized through ultrasonic and solvothermal processes and its structure confirmed by spectroscopy (IR), ultraviolet-visible spectrum (UV–Vis) and powder X-ray diffraction analysis (PXRD). Structural characterization of the complex was performed through single-crystal X-ray diffraction and thermal stability of it was perused via thermogravimetric analysis (TGA). The title Cu(II) complex was used as an effective sensor for H2O2. The electrochemical method is one of the most effective methods for material sensing. In many electrochemical techniques to increase the efficiency of activity, the electrochemically active agent is supported on a substrate. Instead of using substrate, the chemical active agent can be applied as a part of the complex structure. In this work, ferrocene dicarboxylate as an active agent in the Cu(II) complex has been used for sensing of H2O2. Due to the effect of particle size on electrochemical activity, the nano-sized complex was synthesized by ultrasonic technique (as an environmentally friendly method) and also, CuO nanoparticles were also obtained by thermal decomposition of ultrasonic treated complex at 500 °C. The size and morphology of the nanoparticles were explored by scanning electron microscopy (SEM). As well as, they were characterized through X-ray diffraction (XRD) and elemental mapping.

The catalyst operation of four metal-organic frameworks (MOFs), [Zn(oba)(4-bpmb) 0.5 ] n ·(DMF) 1.5 (TMU-6), [Zn(oba)(R-4-bpmb) 0.5 ] n ·(DMF) 1.5 (R-TMU-6), [Zn(oba)(4-bpmn) 0.5 ] n ·(DMF) 1.5 (TMU-21) and [Zn(oba)(R-4-bpmn) 0.5 ] n ·(DMF) 1.5 (R-TMU-21) containing phenyl and naphthyl derivatives, respectively, is discussed. These compounds were easily prepared via mechanosynthesis and utilized for catalysis of the Knoevenagel reaction. The effect of reduction and nature of N-donor pillar ligands resulting different characteristics are investigated on the catalytic performance of the MOFs. Using various aromatic aldehydes, the catalytic activity seems to be enhanced by increased N-donor ligands basicity. Results show that among the four compounds, R-TMU-21 with the most basic center reaction bearing naphtyl-containing pillar has the highest catalytic activity.

Nanostructures of a metal-organic framework with chemical formula, [Co(BDC)(L*)]n.DMF (TMU-40), BDC = 1,4-benzendicarboxylate, L* = 5,6-dipyridin-4-yl-1,2,3,4-tetrahydropyrazine, under ultrasonic irradiation at ambient temperature and atmospheric pressure were prepared and characterized by Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Sonication time, concentration of initial reagents and ultrasonic generator power effects on the size and morphology of nano-structured compounds were studied. TMU-40 (for Tarbiat Modares University) displayed a good potential as a luminescent sensor against phenol derivatives consist of phenol, 4-aminophenol, 4-methylphenol and 4-chlorophenol. Nano-sized TMU-40 showed the better sensing performance in comparison to its bulk phase. The nano TMU-40 displayed very selective and sensitive in detection of phenol derivatives. The detection limit amounts of 15 nM and 63 nM were achieved for 4-aminophenol in nano TMU-40 and bulk TMU-40, respectively. The special structure and fluorescent character of L* ligand and high surface area of nano MOF provide an effective interaction between MOF and phenolic analytes to selectively and sensitively detect of the analyte molecules.

Two new zinc(II) coordination polymers, [Zn(Quinoxaline)(NO3)2(H2O)2]n⋅Quinoxaline·H2O (1) and [Zn(Quinoxaline)2(Br)2]n (2), Quinoxaline = Benzopyrazine, have been synthesized and characterized by IR spectroscopy. Compounds 1 and 2 were structurally characterized by single crystal X-ray diffraction and are one-dimensional coordination polymers with coordination environment of octahedral and tetrahedral respectively. Nanostructures of zinc(II) oxide were obtained by thermolyses of compound 1 in oleic acid, calcination of compound 1 at 500 °C under air atmosphere and sol–gel processes. Also, nanopowders of zinc(II) oxide were obtained by calcination of compound 2 at 450 and 550 °C. The nanomaterials were characterized by scanning electron microscopy and X-ray powder diffraction (XRD). The thermal stability of compounds 1 and 2 both their bulk were studied by thermo-gravimetric (TGA) and differential thermal analyses (DTA). This study demonstrates the coordination polymers may be suitable precursors for the preparation of nanoscale materials.

A new coordination polymer, [Zn2Na4(CH3COO)8H2O]n (1) has been synthesized and characterized by IR spectroscopy. The single crystal X-ray data of compound 1 shows that this coordination polymer grows in two dimensions. Also, the ZnO nanoparticles has been synthesized by thermolysis of compound 1 in oleic acid, calcination at 500 and 600 °C under air atmosphere and sol–gel processes. Nanoparticles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Thermal stability of compound 1 was carried out by thermal gravimetric (TG) and differential thermal analysis (DTA). The zinc(II) oxide nanoparticles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).

A new Mn(II) coordination polymer, [Mn(L1)2(N3)2]n (1), L1 = 3,4-bis(4-pyridyl)-5-(2-pyridyl)-1,2,4-triazole, was synthesized by the reaction of ligand L1 and mixtures of manganese(II) acetate and sodium azide via branched tube method. Compound 1 was structurally characterized by single-crystal X-ray diffraction. The results show that 1 is a 1D helix coordination polymer. Also nanostructures of 1 have been prepareded by sonochemical process at ambient temperature. The effects of two different concentrations of initial reagents on the size and morphology of the nanoparticles were studied and the products were characterized by X-ray powder diffraction and scanning electron microscopy (SEM). Also the comparison of the thermal stability of bulk form and nanoparticles of 1 was investigated by thermal gravimetric and differential thermal analyses.

Two zinc(II) coordination polymers, {[Zn(3-bpdb)(NO2)]·0.5H2O} n (1) and [Zn(4-bpdb)(NO2)2] n (2), 3-bpdb = 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene and 4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene}, have been synthesized and characterized by elemental analyses and IR spectroscopy. Nanoparticles of zinc(II) oxide have been prepared by thermolyses of two different zinc(II) coordination polymers, 1–2. The nano-materials were characterized by scanning electron microscopy, X-ray powder diffraction and IR spectroscopy. The thermal stability of ZnO nano-particles was studied by thermal gravimetric and differential thermal analysis and showed that there is no loss of weight, which indicates that the products were zinc(II) oxide. This study demonstrates the coordination polymers may be suitable precursors for the preparation of nanoscale materials.

Three zinc(II) nitrite coordination polymers, [Zn(4-bpdb)(NO2)2]n (1), {[Zn(3-bpdb)(NO2)]·0.5H2O}n (2) and [Zn(3-bpdh)(NO2)2]n (3), 4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene, 3-bpdb = 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene and 3-bpdh = 2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene} were prepared and characterized by elemental analyses and IR spectroscopy. Compound 3 was structurally characterized by single-crystal X-ray diffraction and is one-dimensional polymer with coordination environments of distorted octahedral, ZnN2O4. The thermal stabilities of compounds 1–3 were studied by thermal gravimetric (TG) and differential thermal analyses (DTA). Direct calcination of the compounds 1–3 at 600 °C under air atmospheres yields different morphologies of nano-sized ZnO.

A new zinc(II) nitrite coordination polymer, [Zn(3-bpdh)(NO2)2]n (1), 3-bpdh = 2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene} was prepared and characterized by elemental analyses and IR spectroscopy. Compound 1 was structurally characterized by single-crystal X-ray diffraction and is one-dimensional polymer with coordination environment of distorted octahedral, ZnN2O4. Thermal decomposition of this precursor in oleic acid at 240 °C under air atmosphere results in the formation of nanoparticles of ZnO. The nano-materials were characterized by scanning electron microscopy, X-ray powder diffraction (XRD) and IR spectroscopy. The thermal stability of nano-structure ZnO was studied by thermal gravimetric and differential thermal analyses and showed that there is no reportable loss of weight in the TGA curves that proves the existence of zinc(II) oxide. This study demonstrates the coordination polymers may be suitable precursors for the preparation of nanoscale materials.