Hydrothermal Synthesis and Structural Characterization of Two Organic–Inorganic Hybrids Based on Sandwich-type Polyoxometalates

Abstract  Two novel inorganic–organic hybrid sandwich-type phosphotungstates [H₂en][Ni(en)₂]₂[{(α-B-PW₉O₃₄)₂Ni₄(H₂O)₂}{Ni(en)₂(H₂O)}₂] · 5H₂O (1) and [Ni(en)₂][Ni(en)₂(H₂O)₂][{(α-B-PW₉O₃₄)₂Ni₄(Hen)₂}{Ni(en)₂(H₂O)}₂] · 10H₂O (2) (en = ethylenediamine) have been synthesized by the hydrothermal reactions of trivacant precursors Na₉[α-A-PW₉O₃₄] · 7H₂O/Na₁₂[α-P₂W₁₅O₅₆] · 18H₂O with NiCl₂ · 6H₂O in the presence of en and structurally characterized by IR spectra, elemental analyses and thermogravimetric analyses. X-ray crystallographic analyses indicate that 1 is made up of inorganic polyoxoanions [Ni₄(H₂O)₂(α-B-PW₉O₃₄)₂]^10– decorated by nickel-organoamine groups, while 2 is constructed from inorganic–organic hybrid polyoxoanions [(α-B-PW₉O₃₄)₂Ni₄(Hen)₂]^8– decorated by nickel-organoamine groups. Graphical Abstract   Hydrothermal Synthesis and Structural Characterization of Two Organic–Inorganic Hybrids based on Sandwich-type Polyoxometalates Bing Li, Zhao Dan, Shou-Tian Zheng, Guo-Yu Yang      

Rare-Earth–Transition-Metal Organic–Inorganic Hybrids Based on Keggin-type Polyoxometalates and Pyrazine-2,3-dicarboxylate

Five rare-earth–transition-metal (RE–TM) heterometal organic–inorganic hybrids based on Keggin-type silicotungstates and mixed ligands H2pzda (pzda=pyrazine-2,3-dicarboxylate) and en (en=ethylenediamine) (enH2)[Cu(en)2(H2O)]2{[Cu(en)2][Cu(en)2(H2O)][(α-SiW11 O39)RE(H2O)(pzda)]}2⋅n H2O (n≈4; RE=YIII ( 1 ), DyIII ( 2 ), YbIII ( 3 ), and LuIII ( 4 )) and [Cu(en)2(H2O)]2{[Cu(en)2]2[Cu(pzda)2][(α-H2SiW11O39)Ce(H2O)]2}⋅n H2O ( 5 ; n≈8) have been hydrothermally synthesized and structurally characterized. Compounds 1–5 all contain the dimeric mono-RE substituted Keggin [RE(α-SiW11O39)]210− subunits linked by H2pzda ligands. Interestingly, 1–4 exhibit discrete structures, in which the H2pzda ligand acts as a tetradentate ligand to bind the RE and Cu cations, whereas 5 displays a 1D double-chain architecture, in which the H2pzda ligand adopts a new pentadentate mode to connect the Ce and Cu cations. To our knowledge, 1–5 represent the first monovacant Keggin-type silicotungstates containing both RE–TM heterometals and mixed ligands. The luminescence of 2 is derived from the combination of the DyIII cations and H2pzda ligands, whereas the luminescence properties of 1 and 3–5 are attributable to the H2pzda ligands.     

An Organic–Inorganic Hybrid Cathode Based on S–Se Dynamic Covalent Bonds

A diphenyl trisulfide–selenium nanowire (DPTS-Se) organic–inorganic hybrid cathode material is presented for rechargeable lithium batteries. During discharge, three voltage plateaus associated with three lithiation processes are observed. During recharge, the combination of the radicals formed upon delithiation leads to several new phenyl sulfoselenide compounds which are confirmed by HPLC-QTof-MS. The hybrid cathode exhibits superior cycling stability over pristine Se or DPTS as cathode alone. The first discharge shows a capacity of 96.5 % of the theoretical specific capacity and the cell retains 69.2 % of the initial capacity over 250 cycles. The hybrid cathode also shows a high Coulombic efficiency of over 99 % after 250 cycles. This study demonstrates that the combination of organic polysulfide and selenium can not only improve the utilization of active materials but also enhance the cycling performance.     

Assembly of Organic–Inorganic Hybrids From 1D to 2D Framework Based on Triethanolamine-Functionalized Molybdovanadate with Electrochemical Sensing of Ascorbic Acid

Journal of Cluster Science - Two new organic–inorganic hybrids, (TeaH)2[Cu(Tea)(H2O)2]2[Cu(Tea)]2[HN(CH2CH2O)3VMo6O22]2·12H2O (1),...     

The First Organic–Inorganic Hybrid Compound Based on Polyoxotungstates and Alkali-tris(imidazolyl) Segments with Electrocatalytic Activity

The first organic–inorganic hybrid compound based on the Keggin polyoxometalate and alkali-N-heterocycle ligand [Na₄(tib)₂(H₂O)₂(α-HBW₁₂O₄₀)]·2H₂O (1) (tib = 1,3,5-tris(1-imidazoly)benzene) was hydrothermally synthesized by utilizing a pH-dependent approach in the POM/Cu/tib reaction systems. X-ray structural analyses reveal that compound 1, formed in pH 5.2, possesses a (3,4,6)-connected 2D net with the (4²·5)(4⁶)(3³·4⁶·5²·6⁴) topology. In addition, electrochemical and electrocatalytic properties of compound 1 were studied by cyclic voltammograms. Compound 1 displayed electrocatalytic activities toward reduction of nitrite.     

Two Novel Organic–Inorganic Hybrid Compounds Constructed from Anderson-type Clusters and Transition-Metal Complexes

Abstract  Two organic–inorganic hybrid compounds based on the Anderson-type clusters [TeMo₆O₂₄]⁶⁻, [(H₂O)₂Co(TeMo₆O₂₄)][(C₁₀N₂H₁₀)₂] · 9.5H₂O (1), [(C₁₀N₂H₉)Ni(H₂O)₃]₂[TeMo₆O₂₄] · 8.5H₂O (2), have been synthesized by hydrothermal reactions and characterized by elemental analyses, IR spectra, thermal stability analyses, and single-crystal X-ray diffraction. Compound 1 displays a 1D chain structure constructed from alternating [TeMo₆O₂₄]⁶⁻clusters and Co²⁺ along the a axis with two pendant ligands 4,4′-bpy (4,4′-bipyridine). Compound 2 is composed of [TeMo₆O₂₄]⁶⁻ clusters coordinated by [Ni(bpy)(H₂O)₃]²⁺ moieties, and a supramolecular architecture is further formed through extensive hydrogen bonds interactions. Graphical Abstract  Two organic–inorganic hybrid compounds based on the Anderson-type clusters [TeMo₆O₂₄]⁶⁻and the unit [M(4,4′-bpy)] have been synthesized under the hydrothermal conditions. Compound 1 displays a 1D chain structure constructed covalently from alternating polyoxoanions [TeMo₆O₂₄]⁶⁻ and Co²⁺ along the a axis with two pendant ligands 4,4′-bipyridine. Compound 2 is composed of [TeMo₆O₂₄]⁶⁻ polyoxoanion coordinated by [Ni(bpy)(H₂O)₃]²⁺ moieties and shows a 1D chain structure through the hydrogen bonds interactions. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

pH-Dependent Assembly of Two Novel Organic–inorganic Hybrids Based on Vanadoantimonate Clusters

Two novel organic–inorganic hybrid vanadoantimonate compounds, [Zn₂(dien)₃][{Zn(dien)}₂V₁₆Sb₄O₄₂(H₂O)]·4H₂O (1) and [Zn(dien)₂]₂ [{Zn(dien)}₂(V₁₄Sb₈O₄₂)₂(H₂O)]·4H₂O (2) (dien = Diethylenetriamine), have been synthesized hydrothermally at different pH value, and structurally characterized by elemental analyses, FT-IR, XPS, TGA and single crystal X-ray diffraction analysis. Compound 1 is composed of the rare [V₁₆Sb₄O₄₂]⁸⁻ cluster covalently linked by two [Zn(dien)]²⁺ coordination cations to yield a novel one-dimensional linear chain. Compound 2 exhibits a one-dimensional zigzag chain constructed from the [V₁₄Sb₈O₄₂]⁴⁻ cluster and [Zn(dien)]²⁺ coordination polymer. The two examples represent the first one-dimensional assemblies based on vanadoantimonate cluster and the metal–organic complex moieties.     

BN- and BO-Doped Inorganic–Organic Hybrid Polymers with Sulfoximine Core Units

While polysulfones constitute a class of well-established, highly valuable applied materials, knowledge about polymers based on the related sulfoximine group is very limited. We have employed functionalized diaryl sulfoximines and a p-phenylene bisborane as building blocks for unprecedented BN- and BO-doped alternating inorganic–organic hybrid copolymers. While the former were accessed by a facile silicon/boron exchange protocol, the synthesis of polymers with main-chain B–O linkages was achieved by salt elimination.     

Hydrothermal Synthesis,Crystal Structure,and Catalytic Performance of Four Organic–Inorganic Hybrids Based on Polyoxometalates and O/N-Containing Groups

Four new network organic–inorganic hybrid supramolecular compounds [PW₁₂O₄₀](C₂H₄N₃)₃·6H₂O (1), [PMo₁₂O₄₀](C₂H₄N₃)₃·6H₂O (2), [H₄SiW₁₂O₄₀]₈[C₆NO₂H₄]₄[C₆NO₂H₅]₁₆[C₅NH₆]₄·39H₂O (3) and [H₃VW₁₂O₄₀] (C₆H₆NO₂)₂(CHO₂)₂·4H₂O (4) composed by keggin type heteropolyanion and O/N-containing organic groups of 1H-1,2,4-Triazole or 2,3-Pyridinedicarboxylic acid have been successfully synthesized by hydrothermally method, and characterized by infrared spectrum (IR), thermogravimetric–differentialthermal analysis (TG–DTA), cyclic voltammetry (CV) and single crystal X-ray diffraction (XRD). Compounds 1–4 exhibit three dimensional supramolecular network via hydrogen bonds and/or π–π stacking interactions. These compounds exhibit good thermal stability and catalytic ability. They are active for catalytic oxidation of methanol in a continuous-flow fixed-bed micro-reactor, when the initial concentration of methanol is 2.5 g m^?3 in air and flow rate is 10 mL min^?1, the corresponding elimination rates of methanol are 65% (125 °C), 85% (125 °C), 94% (150 °C), and 80% (125 °C), respectively.     

Multiphotochromic Systems Based on Hybrid Organic–Inorganic Nanoparticles as “Super-Photochromes” for Photonic Molecular Logic Gates

High Energy Chemistry - When photochromes function as a photonic molecular logic gate (MLG), the problem of uncertainty of the final state of the gate arises at the level of a single molecule,...     

Syntheses,Crystal Structure,Theoretical Calculation and Photophysical Properties of one Inorganic–Organic Hybrid Frameworks Based on Mixed Ligands

Journal of Cluster Science - One novel Inorganic–Organic Hybrid compound [Pb(mip)(bidc)]n (1) [mip?=?2-(3-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline,...     

Syntheses,Crystal Structures and Properties of Organic–Inorganic Hybrid Compounds of 4,4′-Bipyridine–Decorated Ni/Cu-Substituted Molybdophosphates

Organic–inorganic hybrid compounds of transition metal mono-substituted molybdophosphates, (H₂bipy)₂[PNi(Hbipy)Mo₁₁O₃₉]·4H₂O (1), (H₂bipy)_1.5[HPCu(Hbipy)Mo₁₁O₃₉]·4H₂O (2) (bipy = 4,4′-bipyridine), were synthesized hydrothermally and characterized by elemental analysis, IR spectroscopy, TGA, fluorescent spectroscopy, powder and single crystal X-ray diffraction methods. In 1 and 2 the transition metal atom (Ni and Cu) occupies one site of twelve molybdenum atoms of Keggin anion and combines a monoprotonated bipyridine molecular cation, Hbipy⁺, forming a 4,4′-bipyridine–decorated M-substituted molybdophosphate anion (M = Ni and Cu). In 1 two anions form a dimer through hydrogen bonds, in 2 the anions form a chain through hydrogen bonds. The dimers or the chains, H₂bipy²⁺ cations and lattice water molecules are connected by hydrogen bonds, giving supramolecular compounds. The two kinds of bipy molecules, coordinated and uncoordinated, in 1 and 2 give two emission peaks in their photoluminescent spectra.     

Synthesis,Characterization and Crystal Structures of Two New Compounds of Polyoxometalates and Diaminocyclohexanetetraacetate–Copper Complexes

The two new compounds (NH₄)₂[Cu₅(H₂O)₁₀(DCTA)₂] [β-Mo₈O₂₆]·4H₂O (1) and Cu₂[Cu₃K₂(H₂O)₁₀(DCTA)₂(HBW₁₂O₄₀)]·14H₂O (2) (DCTA = 1,2-diaminocyclohexanetetraacetate anion) were synthesized in aqueous solutions and characterized by elemental analyses, TGA, IR spectroscopy and single-crystal X-ray diffraction technique. Single-crystal structure analyses indicate they are constructed by the complexes with different nuclearity and polyoxometalates. In 1 DCTA chelates Cu2 ion and bridges Cu1 and Cu3 ions, forming a tetra-nuclear-ring cation chain extending along [110] direction. In 2 DCTA chelates Cu2/Cu1 and combines Cu3 and K ions, leading to a cyclic ten-heteronuclear complex cation; the K2 ions combine the complex cations and BW₁₂O₄₀ ^5? anions, forming a complex cation-BW₁₂ layer extending on ab-plane. The variable-temperature magnetic susceptibilities of newly prepared crystalline sample of 1 were measured and 1 exhibits a weak antiferromagnetic interaction.     

Stability of Suspensions of Bioactive Particles Using Hybrid Organic–Inorganic Solutions as Dispersing Media

Functional coatings incorporating different types of particles developed by the sol–gel method have been proposed in the last few years for diverse applications. This work focuses on the preparation of homogeneous coatings prepared from stable suspensions with 10 wt% of glass and glass ceramic particles in a hybrid organic–inorganic solution as dispersing media. For this purpose, the pH was shifted up to 6–7 by adding tetrapropylammonium hydroxide (TPAH) which behaves as a cationic surfactant being probably adsorbed on the particles surface, while the sol maintains stable. Rheological measurements were performed to study the stability of the suspensions prepared at different conditions such as the kind and concentration of dispersant and the pH conditions. After sintering at 450^∘C/30 min, coatings around 2 μ m in thickness were obtained.     

An Organic–Inorganic Hybrid Exhibiting Electrical Conduction and Single-Ion Magnetism

The first three-dimensional (3D) conductive single-ion magnet (SIM), (TTF)₂[Co(pdms)₂] (TTF=tetrathiafulvalene and H₂pdms=1,2-bis(methanesulfonamido)benzene), was electrochemically synthesised and investigated structurally, physically, and theoretically. The similar oxidation potentials of neutral TTF and the molecular precursor [HNEt₃]₂[M(pdms)₂] (M=Co, Zn) allow for multiple charge transfers (CTs) between the SIM donor [M(pdms)₂]ⁿ⁻ and the TTF^.+ acceptor, as well as an intradonor CT from the pdms ligand to Co ion upon electrocrystallisation. Usually TTF functions as a donor, whereas in our system TTF is both a donor and an accepter because of the similar oxidation potentials. Furthermore, the [M(pdms)₂]ⁿ⁻ donor and TTF^.+ acceptor are not segregated but strongly interact with each other, contrary to reported layered donor–acceptor electrical conductors. The strong intermolecular and intramolecular interactions, combined with CT, allow for relatively high electrical conductivity even down to very low temperatures. Furthermore, SIM behaviour with slow magnetic relaxation and opening of hysteresis loops was observed. (TTF)₂[Co(pdms)₂] ( 2-Co ) is an excellent building block for preparing new conductive SIMs.     

Role of Counteranions in Sol–Gel-Derived Alkoxyl-Functionalized Ionic-Liquid-Based Organic–Inorganic Hybrid Coatings for SPME

Three alkoxyl-functionalized ionic liquids, 1-(3-triethoxysilyl propyl)-3-methyl imidazolium hexafluorophosphate (TESPMIM[PF₆]), 1-(3-triethoxysilyl propyl)-3-methyl imidazolium tetrafluoroborate (TESPMIM[BF₄]), and 1-(3-triethoxysilyl propyl)-3-methyl imidazolium bis(trifluoromethanesulfonyl)imide (TESPMIM[N(SO₂CF₃)₂]), were synthesized and used as selective coating materials to prepare chemically bonded ionic-liquid-based organic–inorganic hybrid solid-phase microextraction (SPME) fibers by sol–gel technology. A possible mechanism of the sol–gel process is proposed, and the successful binding of ionic liquids to the formed silica substrate was confirmed by Fourier-transform infrared spectroscopy (FT-IR). These ionic-liquid-based sol–gel coatings have porous surface structure, high thermal stability, strong solvent resistance, wide pH application range, good coating preparation reproducibility, special selectivity, and extraction efficiency for both polar and nonpolar compounds, such as phenolic environmental estrogens, fatty acids, aromatic amines, alcohols, phthalate esters, and polycyclic aromatic hydrocarbons. The TESPMIM[PF₆]- and TESPMIM[BF₄]-coated fibers have much lower thermal stability (to 300 and 285 °C, respectively) than TESPMIM[N(SO₂CF₃)₂]-coated fiber (to 454 °C). However, the selectivity of these two fibers is higher towards strong polar analytes, while lower towards medium polar or nonpolar analytes compared with TESPMIM[N(SO₂CF₃)₂]-based fiber. This could be explained by the fact that different counteranions in ionic liquid structures have different steric hindrance, nucleophilicity, hydrophobicity, and ability to form hydrogen bonds, resulting in significant difference in the characteristics of the ionic-liquid-based SPME fibers, such as the surface morphology, thermal stability, selective extraction ability, etc. This work demonstrates that the performance of the ionic-liquid-based coatings can be simply tuned by changing the counteranions incorporated into the ionic liquid structures.

     

Role of Counteranions in Sol–Gel-Derived Alkoxyl-Functionalized Ionic-Liquid-Based Organic–Inorganic Hybrid Coatings for SPME

Three alkoxyl-functionalized ionic liquids, 1-(3-triethoxysilyl propyl)-3-methyl imidazolium hexafluorophosphate (TESPMIM[PF₆]), 1-(3-triethoxysilyl propyl)-3-methyl imidazolium tetrafluoroborate (TESPMIM[BF₄]), and 1-(3-triethoxysilyl propyl)-3-methyl imidazolium bis(trifluoromethanesulfonyl)imide (TESPMIM[N(SO₂CF₃)₂]), were synthesized and used as selective coating materials to prepare chemically bonded ionic-liquid-based organic?Cinorganic hybrid solid-phase microextraction (SPME) fibers by sol?Cgel technology. A possible mechanism of the sol?Cgel process is proposed, and the successful binding of ionic liquids to the formed silica substrate was confirmed by Fourier-transform infrared spectroscopy (FT-IR). These ionic-liquid-based sol?Cgel coatings have porous surface structure, high thermal stability, strong solvent resistance, wide pH application range, good coating preparation reproducibility, special selectivity, and extraction efficiency for both polar and nonpolar compounds, such as phenolic environmental estrogens, fatty acids, aromatic amines, alcohols, phthalate esters, and polycyclic aromatic hydrocarbons. The TESPMIM[PF₆]- and TESPMIM[BF₄]-coated fibers have much lower thermal stability (to 300 and 285?°C, respectively) than TESPMIM[N(SO₂CF₃)₂]-coated fiber (to 454?°C). However, the selectivity of these two fibers is higher towards strong polar analytes, while lower towards medium polar or nonpolar analytes compared with TESPMIM[N(SO₂CF₃)₂]-based fiber. This could be explained by the fact that different counteranions in ionic liquid structures have different steric hindrance, nucleophilicity, hydrophobicity, and ability to form hydrogen bonds, resulting in significant difference in the characteristics of the ionic-liquid-based SPME fibers, such as the surface morphology, thermal stability, selective extraction ability, etc. This work demonstrates that the performance of the ionic-liquid-based coatings can be simply tuned by changing the counteranions incorporated into the ionic liquid structures.     

Crown Inorganic–Organic Hybrid Composed of Copper-Amino Acid Rings and the Classical Keggin Polyoxoanions

A new crown inorganic–organic hybrid material composed of the Keggin polyoxometalates and transition metal-amino acid coordination complexes, K₂{[KCu₄(gly)₄(OH)₂(H₂O)₂Cl][PW₁₂O₄₀]}₂·19H₂O (1), was synthesized and characterized by elemental analysis, IR spectroscopy, TG analysis and single crystal X-ray diffraction. Compound 1 possesses of a 1D chain structure with a crown-type monomer, which is built up from [PW₁₂O₄₀]^3? building blocks and tetranuclear [KCu₄(gly)₄(OH)₂(H₂O)₂Cl] rings. The [KCu₄(gly)₄(OH)₂(H₂O)₂Cl] ring consists of four Cu²⁺ ions and four gly ligands, which exhibits the crown ether feature binding a potassium ion in its center. Further, two [KCu₄(gly)₄(OH)₂(H₂O)₂Cl] rings linked two Keggin polyoxoanions [PW₁₂O₄₀]^3? into crown inorganic–organic hybrid material. Magnetic study shows the existence of ferromagnetic interactions in compound 1.