Organic–Inorganic Incompletely Condensed Polyhedral Oligomeric Silsesquioxane-Based Nanohybrid: Synthesis,Characterization and Dye Removal Properties

A nanocomposite was developed from organic–inorganic hybrid of incompletely condensed polyhedral oligomeric silsesquioxane nanoparticles and poly (acrylamide-co-hydroxyethyl methacrylate) with properties of hydrophobicity of incompletely condensed polyhedral oligomeric silsesquioxane and dye adsorption capacity of the copolymer. The as-prepared nanocomposites were characterized by X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. The synthesized hybrid nanocomposite acquires extraordinary water remediation property after the removal of toxic dye from aqueous solution. Conditions for the adsorption of dye by the hybrid nanocomposite have been also optimized. In addition, the adsorption mechanism was studied.     

Hydrothermal Synthesis,Crystal Structure and Electrochemical Property of Two Inorganic–Organic Hybrid Frameworks via Hydrogen Bonding

Two inorganic–organic hybrid frameworks, namely [Cu₂(pdca)₂(bibp)(H₂O)₂]·H₂O (1) and [Fe(pdca)(pyco)(H₂O)]·H₂O (2) (H₂pdca = pyridine-2,6-dicarboxylic acid, bibp = 4,4′-bisimidazolylbiphenyl, pyco = picolinate N-oxide) were synthesized via hydrothermal reactions. Both compounds have been characterized by elemental analysis, spectroscopic analysis, thermogravimetric analysis (TGA) and the single crystal diffraction. Complex 1 is dinuclear and five-coordinated copper(II) complex, while complex 2 displays mono-nuclear and six-coordinated iron(III) complex. In the crystal structures of both complexes, the coordinated and crystalline water molecules and H₂pdca ligands contribute to the formation of O–H···O and C–H···O hydrogen bonds, which link the molecules into layers parallel. Cyclic voltammetry (CV) analysis shows one reversible reduction potential at 0.14 V (E_pc) in complex 1, whereas in complex 2 shows a reduction potential at 0.15 V (E_pc) in the cathodic region.     

Self-Assembled Organic–Inorganic Hybrid Nanocomposite of a Porphyrin Derivative and CdS

A porphyrin derivative, 5-(4-carboxylphenyl)-10,15,20-tris(4-chlorophenyl) porphyrin (PorCOOH), was synthesized and self-assembled as a monolayer thin solid film on the modified surface of a quartz substrate by an ester bond between –COOH groups of PorCOOH molecules and –OH groups of the hydrophilic pretreated SiO₂ surface. An analysis of the spectral change revealed the J-aggregate nature of PorCOOH molecules in the obtained thin solid film. With this thin solid film of PorCOOH as a template, CdS nanoparticles were deposited on it in situ, which were further characterized by electronic absorption, fluorescence, and energy-dispersive X-ray spectroscopy. The morphology of CdS nanoparticles is disklike, and the diameter is ca. 40–60 nm, determined by scanning electronic microscopy. Furthermore, electron transfer between the organic layer and CdS nanoparticles was deduced through fluorescence quenching and theoretical analysis.     

An Organic–Inorganic Hybrid Polymer Based on Molybdenum(V) Phosphate and Cadmium(II) Complex

An unusual organic–inorganic hybrid polymer, [Cd(pztt)(H₂O)₂]₄[CdMo ₁₂ ^V O₂₄(OH)₆ (HPO₄)₄(H₂PO₄)₂(PO₄)₂]·10H₂O (pztt = 3-(pyrazin-2-yl)-5-(1H-1,2,4-triazol-3-yl)-1,2,4-triazliyi) (1), have been hydrothermally synthesized and structurally characterized by the elemental analysis, TG, IR, UV–Vis, PXRD and the single-crystal X-ray diffraction. In compound 1, the sandwich-type {Cd[Mo₆P₄O₃₁]₂} units are modified with Cd(pztt)(H₂O)₂ fragments to lead bi-supported dimer clusters, which are further linked by binuclear complex subunits [Cd₂(pztt)₂(H₂O)₄] to yield unusual 1-D chains. The 1-D chains are further packed into 2-D and 3-D supramolecular assemblies via strong hydrogen-bonding interactions. In addition, the electrochemical behavior of 1-CPE and the photoluminescence properties of 1 in the solid state at room temperature have been investigated in detail.     

Inorganic–Organic Hybrid Materials of Zirconium and Aluminum and Their Usage in the Removal of Methylene Blue

Two novel inorganic–organic hybrid materials, Al-Pydca-3-APDEMS-H and Zr-Pydca-3-APDEMS-H, were prepared by the sol gel method in two steps. In the first step, Al(O^sBu)₂-Pydca and Zr(OPrⁿ)₃-Pydca complexes were prepared from the reactions of aluminum sec-butoxide Al(O^sBu)₃ and zirconium n-propoxide Zr(OPrⁿ)₄ with 2,6-pyridinedicarboxylic acid, respectively. After 3 h of stirring, 3-aminopropyldiethoxymethyl silane (3-APDEMS) and dilute hydrochloric acid were added to the Al(O^sBu)₂-Pydca and Zr(OPrⁿ)₃-Pydca mixtures to hydrolyze the reactions and to form condensation products. These hybrid products were characterized by a combination of Fourier-transform infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray (EDX) spectroscopy, Brunauer–Emmett–Teller (BET) analysis, Barrett-Joyner-Halenda (BJH) and other analysis methods. These hybrid materials were used for the removal of methylene blue (MB), a cationic organic dye. The removal efficiency of hybrid materials was measured by UV–Vis spectroscopy.

     

Ladder-Like Versus Hexagonal Organic–Inorganic Hybrid Materials in the Extraction of Lead Ions

Meso-structured and ladder organic–inorganic hybrid materials functionalized with ammonium carboxylate groups were prepared. These materials were obtained by the sol–gel process starting from the cyanopropyltriethoxysilane precursor as a building block. Hydrolysis of CN to COOH groups followed by treatment with triethylamine gives rise to cationic exchange materials. These materials exhibit a high chelating capability towards cations and can be used for water treatment. Lead ion (Pb²⁺) was tested as example; and, some tests were made on the meso-structured and ladder material for further comparison in efficacy of extractions.     

Ionothermal Syntheses and Crystal Structures of Two 1D Inorganic–Organic Hybrid Frameworks

Two 1D inorganic–organic hybrid frameworks, namely, [Zn(5-NO₂-bdc)(MIM)₃·H₂O]_n(1) and [Cd(MIM)₂Br₂]_n(2) (5-NO₂-bdcH₂ = 5-nitro-1,3-benzenedicarboxylic acid, MIM = N-methyl imidazole) were synthesized via ionothermal reactions with ionic liquid 1-ethyl-3-methylimidazolium bromide ([EMIM]Br) as solvent and template. Both compounds have been characterized by elemental analyses, spectroscopic analyses, thermogravimetric analysis (TGA) and the single crystal diffraction. The zinc(II) center in compound 1 is a slightly distorted five-coordinate trigonal bipyramid, 5-NO₂-bdc²⁻ anions and MIM moieties effectively bridge Zn centers to result in 1D zigzag chains. While Cd(II) center in compound 2 is in an octahedral coordination environment, and two μ²-bridge bromine link two [Cd(MIM)₂] moieties to form a 1D chain structure. In addition, complex 2 exhibits strong fluorescent emission in the solid state at room temperature.     

Synthesis and Characterization of pH-Responsive Organic–Inorganic Hybrid Material with Excellent Catalytic Activity

Poly(N-isopropylmethacrylamide-co-methacrylic acid) [p(NipAam-Mac)] microgels were synthesized and used as microreactors to fabricate silver nanoparticles. Pure and hybrid microgels were characterized using Ultraviolet–Visible (UV/Vis) spectroscopy, Fourier transform infra-red (FTIR) spectroscopy and transmission electron microscopy (TEM). Catalytic activity of hybrid microgels and mechanism of catalysis by this system was explored using different reaction conditions. At the same temperature, apparent rate constant (k_app) was found to be varied from 0.0414 to 0.7852 min^?1 by increasing the concentration of NaBH₄ from 2.49 to 22.41 mM at constant concentration of substrate and catalyst. However upon extra increase in concentration of NaBH₄ from 22.41 to 37.35 mM reduced the value of k_app to 0.2178 min^?1. Likewise, the value of k_app was found to be increased from 0.1242 to 0.5495 min^?1 with increasing the concentration of 4-nitrophenol [Para-nitrophenol (p-Np)] from 0.063 to 0.079 mM keeping other parameters constant. Further increase in concentration of p-Np caused decline in the value of k_app. Kinetic data reveals that catalytic reduction of p-Np obeys Langmuir–Hinshelwood mechanism and p-Np is converted to p-Ap on the surface of the silver nanoparticles passing through various reaction intermediates.     

A New 3D Pb(II) Inorganic–Organic Hybrid Framework Based on Terephthalate Acid with the Inorganic Pb–O–Pb Connectivity

Solvothermal reaction of Pb(NO₃)₂ with terephthalate acid afforded one new inorganic–organic hybrid framework, [Pb(PBDC)]_n (1) (H₂PBDC = terephthalic acid). X-ray analysis shows that compound 1 crystallizes in orthorhombic space group Pbca and the two carboxy group of terephthalate acid adopt rare coordination modes. A noticeable point in this paper that compound 1 exhibits preferable catalytic property on degradation of Rhodamine B. The phase purity of the as-synthesized sample was confirmed by powder X-ray diffraction. Moreover, satisfactory elemental analysis, IR spectra, and thermogravimetric analysis were obtained.     

A Luminescent Rod-Packing Organic–Inorganic Hybrid Framework Based on Copper(I) Cyanide Ribbon and 5-(4-Pyridine)tetrazole Ligand

The hydrothermal reaction of CuCN, K₃Fe(CN)₆ and 5-(4-pyridine)tetrazole generated a novel three-dimensional organic–inorganic hybrid framework, namely, {Cu₃(5PyTAZ)(CN)₂} _n (1) (5PyTAZ = 5-(4-pyridine)tetrazole). X-ray single-crystal diffraction shows that two independent Cu(I) centers are four-coordinate tetrahedral and three-coordinate trigonal geometries, which are connected by μ ₃-CN groups to form a 1D [Cu₃(CN)₂] _n inorganic ribbon along the c-axis direction. Each 5PyTAZ ligand links four adjacent inorganic ribbons via its five N-atoms to generate a complex 3D hybrid structure. If the 1D copper(I) cyanide ribbon was regarded as rod-shape building block, 1 exhibits a simple rod-packing topological framework. Furthermore, 1 is characterized by X-ray powder diffraction, elemental analysis, FT-IR, Raman spectra and TG/DTA. Notably, solid-state luminescence measurements indicate that 1 is a potential photoluminescence material.     

An Efficient and Recyclable Silica Based Inorganic–Organic Hybrid Zinc Catalyst for Transesterification of β-Ketoesters

A new silica based inorganic–organic hybrid zinc catalyst was synthesized and its catalytic activity was investigated for transesterification of β-ketoesters. Polymer supported catalyst was characterized by various techniques such as surface area (BET), elemental and thermogravimetric analyses, FTIR, ¹³C CPMAS spectral studies and atomic absorption spectroscopy (AAS). The reaction proceeded smoothly in the presence of 0.04 mmol of catalyst in toluene at refluxing conditions. The catalyst revealed higher catalytic activity compared to homogeneous catalyst and was reused without appreciable loss in catalytic activity.     

Syntheses and Crystal Structures of Two Inorganic–Organic Hybrid Frameworks Constructed from Pyridine-2,5-Dicarboxylic Acid

Two novel inorganic–organic hybrid frameworks of [Co(2,5-pydc)(4,4′-bipyo)_0.5(H₂O)₃ · 3H₂O] _n (1) and [Cu_1.5Gd(2,5-pydc)₃(2,2′-bipyo)(H₂O)₄ · 2H₂O] _n (2) (2,5-pydc = pyridine-2,5-dicarboxylic acid; 4,4′-bipyo = 4,4′-bipyridine-N,N′-dioxide; 2,2′-bipyo = 2,2′-bipyridine-N,N′-dioxide) were prepared. Both compounds have been characterized by the elemental analyses, IR spectra, TG analysis and the single crystal diffraction. The salient structural feature for both compounds 1 and 2 is that the 1D chain and the mononuclear fragment are connected by strong hydrogen bond interactions to form 2D structure.     

Synthesis,Characterization, Luminescent and Thermal Properties of a Hybrid Inorganic–Organic Polymeric Framework Formed by Lead (II) Pyridinecarboxylate

Abstract  

A coordination polymer of formula [Pb_0.5(pyc)] _n , 1, where Hpyc = pyridine-3-carboxylic acid, has been synthesized and structurally characterized by X-ray single crystal diffraction analysis. Every Pb(II) centre demonstrate trigonal dodecahedron geometry. The ligand i.e. pyridine-3-carboxylate offers μ _{3 -} η ² : η ¹ coordination pattern using its hetero donor centres. The complex initially forms an infinite 1D chain (c-axis) which is turned to 2D sheet and finally a 3D network is recognized through ligand connectivity. Stabilization of 3D structure is further reinforced by π–π stacking interaction. An open channel is identified along c-axis. TG analysis has been performed for the complex. Emission study demonstrates the existence of intraligand and metal-to-ligand charge transfer transition in 1.     

Direct Electrochemistry and Electrocatalysis of Hemoglobin on Bimetallic Au–Pt Inorganic–Organic Nanofiber Hybrid Nanocomposite and Mesoporous Molecular Sieve MCM-41

A glassy carbon electrode modified with MCM-41 and bimetallic inorganic–organic nanofiber hybrid nanocomposite was prepared and used for determination of trace levels of hydrogen peroxide (H₂O₂). The direct electron transfer (DET) and electrocatalysis of hemoglobin (Hb) entrapped in the MCM-41 modified Au–Pt inorganic–organic nanofiber hybrid nanocomposite electrode (Au–PtNP/NF/GCE) were investigated by using cyclic voltammetry in 0.1 M pH 7.0 phosphate buffer solution. Due to its uniform pore structure, high surface area and good biocompatibility, the mesoporous silica sieve MCM-41 provided a suitable matrix for immobilization of biomolecules. The MCM-41 modified Au–Pt inorganic–organic nanofiber hybrid nanocomposite electrode showed significant promotion to DET of Hb, which exhibited a pair of well-defined and quasi-reversible peaks for heme Fe(III)/Fe(II) with a formal potential of ?0.535 V (vs. Ag/AgCl). Additionally, the Hb immobilized on the MCM-41 modified electrode showed excellent electrocatalytic activity toward H₂O₂ reduction.     

Pd(II)/Pd(0) Anchored on Magnetic Organic–Inorganic Hybrid Mesoporous Silica Nanoparticles: A Nanocatalyst for Suzuki–Miyaura and Heck–Mizoroki Coupling Reactions

Journal of Inorganic and Organometallic Polymers and Materials - 3-Chloropropyltrimethoxysilane (CPTMS) was grafted on the surface of silica coated Fe3O4 core (Fe3O4@MCM-41) and then condensed with...     

Synthesis,Characterization, and Application of Hybrid Inorganic–Organic Composites (K/Na)ZrSi(R)O<Subscript>x</Subscript>

Hybrid inorganic–organic composites, (K/Na)ZrSi(R)O_x, were synthesized from the hydrolysis of the mixture of zirconium n-propoxide (Zr(OPrⁿ)₄) and 3-glycidyloxypropyltrimethoxy silane (GPTS) in 1:1 mol ratio. The hydrolysis reaction was carried out with 0.1 molar HCl in 150 ml of butanol. Then, the synthesized Zr(OPrⁿ)₄-GPTS-hydrolyzate reacted with KOBu^t and NaOSiMe₃ in 1:1 mol ratio at 40 and 50 °C for 24 h, respectively. After these stages, composites were washed and dried under vacuum. Composites and their oxide prepared at 1250 °C by calcinations were characterized by a combination of powder X-ray diffraction, scanning electron microscope, energy dispersive X-ray, Brunauer–Emmett–Teller analysis, Barrett–Joyner–Halenda analysis, and Fourier transform infrared spectroscopies. These hybrid inorganic–organic composites except oxides were used as catalysts in order to see their activities in the polymerization of ε-caprolactone (ε-CL). This study showed that new composite materials except their oxides were effective catalyst in ε-CL polymerization.     

New Inorganic–Organic Hybrid Materials and Their Oxides for Removal of Heavy Metal Ions: Response Surface Methodology Approach

In this paper, Cu(II), Fe(III), Pb(II), and Zn(II) heavy metal ions were removed from their aqueous solutions by using novel inorganic–organic hybrid materials, Al-GPTS-H and Al-GPTS-NaOSiMe₃-H (hybrid material-1 and 2, respectively), and their oxides (calcined-1 and 2) as adsorbents. These ions removal by adsorption was optimized by using response surface methodology (RSM). Central composite design (CCD) method was used in order to investigate the effects of initial pH, initial metal concentration of solutions and adsorbent quantity on the adsorption efficiency (R, %). As a result of the experiments under optimum conditions, the maximum % R values were obtained by hybrid material-1 for Fe(III) (99.89%) and by calcined material-1 for Pb(II) (97.14%), respectively. These quite high adsorption efficiency values have shown that these hybrid materials and their oxides are suitable to use for heavy metal ions removal from aqueous solutions.