Sonochemical synthesis of two new zinc(II) 1,10-phenanthroline coordination supramolecular compounds: New precursors to produce nano-sized zinc(II) oxide

Controlled bottom-up synthesis and characterization of crystalline and amorphous lead(II) coordination polymers: Sonochemical methods, structure-property relationship, and photocatalytic applications

The 3D coordination polymers of lead (II) [Pb4(O)(L)3(H2O)]n, where H2L = C6H4(CO2H)2 (benzene-1,3-dicarboxylic acid), were synthesized in crystalline (1(a, b)) and amorphous (2(a, b)) phases. Hydrothermal and branch tube methods were used to self-assemble lead (II) from the bottom up to create the crystalline phases. Single-crystal X-ray diffraction (SC-XRD) was used to investigate two crystallized metal-organic frameworks (MOFs) with the same space group and chemical formula (P21/c). Through controlled green sonochemical methods, an ultrasonic bath and a probe homogenizer were used to prepare nano [Pb4(O)(L)3(H2O)]n in the amorphous phase. An extensive study has been conducted on the effect of initial reagent concentration, ultrasonic power, temperature, reaction time, and surfactant presence on the size and morphology of synthesized nanocoordination polymers. Analyses of the synthesized compounds were performed using scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), FT-IR spectroscopy, and CHNS elemental analysis. By using thermal gravimetry (TGA-DTA), the thermal stability of nanostructures was examined and compared with that of crystalline structures. A Hirschfeld surface and a two-dimensional fingerprint diagram were used to analyze intermolecular interactions in crystalline phases. Photocatalytic degradation of methylene blue was investigated using 1a and 2b_2, which represent the synthetic compounds. Calculation of the band gap of synthesized polymers was conducted using the Tauc diagram (based on the DRS results). During optimal conditions of C0 = 0.6 mg L1, pH = 7, and irradiation time = 60 min, the maximum photodegradation efficiencies of methylene blue (MB) were observed for 1a and 2b_2. In terms of degradation efficiency, 1a's reusability was 73.5 % for the first cycle and 70.6 % for the fifth, while 2b_2's reusability was 88.2 % for the first cycle and 81.7 % for the fifth. These materials can be used in multiple photocatalytic cycles based on the results obtained.

Modulating the structure and photochromic performance of hybrid metal chlorides with nonphotochromic 1,10-phenanthroline and its derivative

Hybrid photochromic materias (HPMs), especially crystalline HPMs (CHPMs), have been widely investigated due to their feasibility in maintaining the advantages of each constituent and genearating captivating photomodulated functionality. Metal-organic complexes (MOCs), as promising candidates for fabricating CHPMs, have attracted the interest of researchers. The molecular predesign of ligands plays a crucial role in yielding MOC-based CHPMs with tunable photochromic functionality. Hitherto, a great majority of CHPMs are driven by photosensitive ligands. However, the complicated synthesis and high cost of photosensitive ligands obviously prevent the macro-synthesis and future application of these CHPMs. Thus, it is indispensable to explore novel branches of CHPMs. Herein, we report a series of photochromic solid materials bearing modulated photochromic properties by hybridizing metal chlorides with a nonphotosensitive coplanar dipyridine unit 1,10-phenanthroline (phen) and its derivative 5-chloro-1,10-phenanthroline (5-Cl-phen). The resulting hybrids, [ZnCl₂(phen)] (1), [CdCl₂(phen)] (2), [PbCl₂(phen)] (3), [ZnCl(H₂O)(5-Cl-phen)₂]Cl·2H₂O (4), [Cd₂Cl₄(5-Cl-phen)₂] (5) and [Pb₂Cl₄(5-Cl-phen)₂] (6), exhibit distinct structures from the isolated molecular complexes (1 and 4) to the hybrid chain (2, 3, 5 and 6) because of the distinct coordination mode of central metal ions and chloride ions. After photo-irradiation with a Xe-lamp, all complexes, as expected, exhibited apparent color change because of the photoinduced electron transfer (ET) between coordinated chloride ions (Cl^-) as electron donors (EDs) and the coordinated coplanar phen and 5-Cl-phen species as electron acceptors (EAs). More importantly, the photochromic performance of the title complexes could be modulated by phen and 5-Cl-phen. This study provides a general and facile way for modulating the structure and photochromic performance of hybrid metal chlorides with phen or phen-based derivatives under the synergy of crystalline engineering strategy and ET mechanism.

A novel high performance nano chemosensor for copper (II) ion based on an ultrasound-assisted synthesized diphenylamine-based Schiff base: Design, fabrication and density functional theory calculations

A novel high selective colorimetric chemosensor was introduced based on a nano diphenyl-based Schiff base (H₂L), 2,2'-((1E,1'E)-(((hexylazanediyl)bis(4,1-phenylene))bis(methanylylidene))bis(azanylylidene))bis(4-methylphenol) that synthesized using sonochemical method. H₂L was characterized by FT-IR, MS, TGA, ¹H NMR, ¹³C NMR, SEM and elemental analysis techniques, then fabricated as the portable strips for sensing copper (II) ions in aqueous media. The binding interaction between H₂L and various metal ions was investigated by UV-Vis spectroscopic that showed favorable coordination toward Cu²⁺ ion. H₂L exhibited binding-induced color changes from yellow to pink and practically no interference in the presence of other metal ions, i.e., Cr²⁺, Mn²⁺, Fe²⁺, Co²⁺, Ni²⁺, Zn²⁺, Cd²⁺, Hg²⁺, Pb²⁺, Mg²⁺ and Ca²⁺. The chemsensor showd the color change from yellow to pink in presence of copper (II) ion in aqueous media due to binging of H₂L and Cu (II). This sensor can determine the copper (II) at in the rang of 7.5 × 10^-8-1.8 × 10^-5 mol L^-1 with a correlation equation: Absorbance = 0.0450[Cu²⁺] × 10^-6 + 0.71 and R² = 0.975 and low detection limit of 1.89 × 10^-8 mol L^-1. Density functional theory (DFT) calculations were carried out at the B3LYP levels of theory with B3LYP/6-311+G(d,p) and LANL2DZ/6-311+G(d,p) basis sets for chemosensor and its copper complex respectively. The optimized geometry, harmonic vibrational frequencies, ¹H NMR and ¹³C NMR chemical, Molecular orbital (M.O.), Mulliken population analysis (MPA), contour of Electrostatic Potential (ESP) and Molecular Electrostatic Potential (MEP) map of H₂L were calculated which show good agreement with behavior of sensor for detection of Cu²⁺ ion.

Sonochemical synthesis and characterization of new seven coordinated zinc, cadmium and mercury nitrate complexes: New precursors for nanostructure metal oxides

The nitrate complexes of group 12 elements with a tridentate Schiff base ligand (L = (E)-N1-((E)-3- phenylallylidene)-N2-(2-((E)-((E)-3-phenylallylidene) amino)ethyl) ethane-1,2-diamine) were synthesized via sonochemical process and characterized by various physical and chemical methods. The structural analysis of the zinc nitrate complex by single crystal X-ray diffraction analysis shows that the central atom is seven-coordinated by three nitrogen atoms from the Schiff base ligand as well as four oxygen atoms from two different nitrate anions. The geometry around the metal center can be described as a distorted pentagonal bipyramid. The crystal packing analysis of zinc nitrate complex indicates that the intermolecular interactions related to nitrate groups plays the essential role in the orientation of supramolecular structure. Hirshfeld surfaces (HS) and their corresponding fingerprint plots (FP) have been also used for further investigation of crystal structure of zinc nitrate complex. Furthermore thermal analyses (TG/DTG) of three nanostructure complexes were carried out and discussed. Finally, direct thermolysis of zinc and cadmium nitrate complexes in air atmosphere led to the production of zinc and cadmium oxide nanoparticles.

Sonochemical synthesis and characterization of a new nano Ce(III) coordination supramolecular compound; highly sensitive direct fluorescent sensor for Cu2

Micro and nano-structures of a new Ce(III) Coordination supramolecular compound, [Ce (1,5-NDS)_1.5(H₂O)₅]_n,1, (1,5-Naphthalenedisulfonic acid), were prepared using hydrothermal and sonochemical approaches, respectively. These new micro and nano structures were characterized by elemental analysis, IR spectra, thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), and powder X-ray diffraction. The X-ray single crystal structure determination of 1 shows that it features a neutral 2D framework based on the [Ce₂H₂₀O₁₆S₂] clusters as a secondary building unit (SBU) which shows a sql/Shubnikov tetragonal plane net. Moreover by considering the H-bonds, the final structure can be considered as 3D supramolecular network. The influence of ultrasound irradiation time on the morphology and size of the nanostructure 1 was investigated. The results indicated that by increasing the time of ultrasonic radiation, smaller nanostructures form and morphological changes occur. Fluorescent properties of the nanoparticles of 1 were also investigated. Coordination polymer 1 shows high fluorescence intensity and good tendency to copper ion that can be used as an optical sensor for selective and sensitive determination of Cu²⁺ in aqueous media with detection limit of 3.0μM.

Two zinc(II) coordination complexes based on an asymmetric multidentate ligand: syntheses, structures, selective fluorescence sensing of iron(III) ions and thermal analyses

The rational selection of ligands is vitally important in the construction of coordination complexes. Two novel ZnII complexes, namely bis(acetato-κO)bis[1-(1H-benzotriazol-1-ylmethyl)-2-propyl-1H-imidazole-κN 3]zinc(II) monohydrate, [Zn(C13H15N5)2(C2H3O2)2]·H2O, (1), and bis(azido-κN 1)bis[1-(1H-benzotriazol-1-ylmethyl)-2-propyl-1H-imidazole-κN 3]zinc(II), [Zn(C13H15N5)2(N3)2], (2), constructed from the asymmetric multidentate imidazole ligand, have been synthesized under mild conditions and characterized by elemental analyses, IR spectroscopy and single-crystal X-ray diffraction analysis. Both complexes exhibit a three-dimensional supramolecular network directed by different intermolecular interactions between discrete mononuclear units. The complexes were also investigated by fluorescence and thermal analyses. The experimental results show that (1) is a promising fluorescence sensor for detecting Fe3+ ions and (2) is effective as an accelerator of the thermal decomposition of ammonium perchlorate.