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Hybrid Organic (hybrid + organic)

Distribution by Scientific Domains
Polymers and Materials Science50%
Chemistry42%

Selected Abstracts

Functional Chromium Wheel-Based Hybrid Organic,Inorganic Materials for Dielectric Applications

ADVANCED FUNCTIONAL MATERIALS, Issue 20 2009
Vito Di Noto
Abstract The first example of organic,inorganic hybrid materials based on the embedding of a chromium,nickel wheel cluster {[(n-C3H7)2NH2]- [Cr7NiF8(O2C4H5)16]} (Cr7Ni) into poly(methyl methacrylate) (PMMA) and the characterization of the dielectric properties of the obtained material is described. By an optimized copolymerization of the methacrylate-functionalized chromium,nickel wheel with methyl methacrylate in a cluster/monomer 1:200 molar mixture, a homogeneous hybrid material CrNi_MMA200 is obtained. The electrical responses of the non-doped PMMA and of the hybrid material were studied by broadband dielectric spectroscopy (BDS) from 0.01,Hz to 10,MHz and over the temperature range of 5,115,°C. The permittivity profiles reveal two relaxation peaks in the materials, which correspond to the , and , relaxation modes of the PMMA matrix. The position of these modes shifts toward higher frequencies as temperature increases. BDS is a powerful tool revealing the intimate miscibility of the various components of the hybrid material, thus indicating that, on a molecular scale, the material proposed is a homogeneous system. Finally, a value of the dielectric constant of 2.9 at 25,°C and 1,kHz is determined. This value is noticeably lower than the value of 3.2 obtained for pristine PMMA prepared following the same synthesis protocol. Thus, these results classify the hybrid CrNi_MMA200 as an appealing starting material for the development of dielectric polymeric layers for the development of innovative capacitors, transistors, and other microelectronic devices. The vibrational properties of the hybrid materials are investigated by Fourier-transform infrared (FT-IR) and Raman spectroscopy, whereas the thermal behavior is analyzed by thermogravimetric analysis (TGA). Swelling experiments are used to qualitatively evaluate the crosslinking density of the hybrid materials. The integrity of the wheels once embedded in the macromolecular backbone is confirmed by extended X-ray absorption fine structure (EXAFS) and electron spin resonance (EPR) spectroscopic measurements. [source]

Hybrid Nanofiber Growth: One-Pot Synthesis of Functional Helicoidal Hybrid Organic,Inorganic Nanofibers with Periodically Organized Mesoporosity (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 18 2009
Mater.
Luminescent nanofibers are grown with controlled alignment of twisted nanochannels, as described by K. Valle and co-workers on page 2896. Tuning of the main synthesis parameters (sol-gel conditions, temperatures, choice of surfactants and inorganic precursors) allows the fine control of morphology, porosity-architecture, and organic chemical functionalization in order to prepare useful functional nanofibers. [source]

One-Pot Synthesis of Functional Helicoidal Hybrid Organic,Inorganic Nanofibers with Periodically Organized Mesoporosity

ADVANCED FUNCTIONAL MATERIALS, Issue 18 2009
Frédéric Rambaud
Abstract The one-pot synthesis and properties of multifunctional hybrid mesoporous organosilica fibers with helical shapes are described. These hybrid mesoporous fibers are prepared without chiral elements and functionalized with a large variety of organic R functions (R,=,alkylthiols, phenylsulfonates, alkylphosphonates, dansyl, aminopropyl, fluoroalkyl, etc.). The resulting nanomaterials are thoroughly characterized by a variety of techniques. The use of a synergetic combination of achiral molecules as co-directing structuring agents, a surfactant, and an organofunctional silica precursor R-Si(OR)3 allows, via carefully tuning of the main synthesis parameters and processing conditions, to control the shape, which is the anisotropic factor, of the hybrid nanofibers. The functionalization of the hybrid materials with fluorescent molecules (dansyl) and gold nanoparticles opens possibilities for sensor and catalytic applications, respectively. Moreover, these hybrid nanofibers can be easily transferred in organic solvents or in a "green" solvent such as water to make stable colloidal dispersions. This tunable functionality of nanofibers also allows their transferability into a variety of polymeric hosts (PVDF, PVBu, and PVP) allowing the formation of functional homogeneous nanocomposite hybrid membranes. [source]

Optically-Pumped Lasing in Hybrid Organic,Inorganic Light-Emitting Diodes

ADVANCED FUNCTIONAL MATERIALS, Issue 13 2009
Myoung Hoon Song
Abstract Here, the use of metal oxide layers both for charge transport and injection into an emissive semiconducting polymer and also for the control of the in-plane waveguided optical modes in light-emitting diodes (LEDs) is reported. The high refractive index of zinc oxide is used to confine these modes away from the absorbing electrodes, and include a nano-imprinted grating in the polymer layer to introduce distributed feedback and enhance optical out-coupling. These structures show a large increase in the luminescence efficiency over conventional devices, with photoluminescence efficiency increased by up to 45%. Furthermore, optically-pumped lasing in hybrid oxide polymer LEDs is demonstrated. A tuneable lasing emission is also obtained in a single device structure by employing a graduated thickness of a zinc oxide inter-layer. This demonstrates the scope for using such architectures to improve the external efficiency of organic semiconductor LEDs, and opens new possibilities for the realization of polymer injection lasers. [source]

Phosphorescent Hybrid Organic,Inorganic Light-Emitting Diodes

ADVANCED MATERIALS, Issue 19 2010
Henk J. Bolink
Competitive efficacy and power conversion efficiency (15,cd,A,1 and above 9,lm,W,1, respectively) are obtained for a hybrid organic,inorganic light-emitting diode (HyLED) with air-stable metal oxides as electrodes. Thanks to the use of a phosphorescent iridium complex and a Cs-doped ZnO cathode, performances approaching those of standard solution-processed organic LEDs can be obtained. [source]

Structure of magnetic poly(oxyethylene),siloxane nanohybrids doped with FeII and FeIII

JOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2003
N. J. O. Silva
Hybrid organic,inorganic nanocomposites doped with FeII and FeIII ions and exhibiting interesting magnetic properties have been obtained by the sol,gel process. The hybrid matrix of these ormosils (organically modified silicates), classed as di-ureasils and termed U(2000), is composed of poly(oxyethylene) chains of variable length grafted to siloxane groups by means of urea crosslinkages. Iron perchlorate and iron nitrate were incorporated in the di-ureasil matrices, leading to compositions within the range 80 ,n, 10, n being the molar ratio of ether-type O atoms per cation. The structure of the doped di-ureasils was investigated by small-angle X-ray scattering (SAXS). For FeII -doped samples, SAXS results suggest the existence of a two-level hierarchical structure. The primary level is composed of spatially correlated siloxane clusters embedded in the polymeric matrix and the secondary, coarser level consists of domains where the siloxane clusters are segregated. The structure of FeIII -doped hybrids is different, revealing the existence of iron oxide based nanoclusters, identified as ferrihydrite by wide-angle X-ray diffraction, dispersed in the hybrid matrix. The magnetic susceptibility of these materials was determined by zero-field-cooling and field-cooling procedures as functions of both temperature and field. The different magnetic features between FeII - and FeIII -doped samples are consistent with the structural differences revealed by SAXS. While FeII -doped composites exhibit a paramagnetic Curie-type behaviour, hybrids containing FeIII ions show thermal and field irreversibilities. [source]

Hybrid 2D and 3D Frameworks Based on ,-Keggin Polyoxometallates: Experiment and Simulation

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 15 2005
Anne Dolbecq
Abstract The ,-Keggin polyoxomolybdate {,-PMoV8MoVI4O40,x(OH)xM4} is a versatile building unit, with M being either a ZnII or a LaIII capping ion located at the vertices of a slightly distorted tetrahedron. The charge of the Keggin unit depends on the number of protonated oxo bridging ligands, which has been shown to vary from 0 to 5. The Keggin entity can thus be either an anion (M = Zn, x = 0) or a cation (M = La, x = 3,5). The Zn derivative has been generated in situ by hydrothermal synthesis and forms a 2D material built from the connection of the cations by 4,4'-bipyridine ligands linked to the capping ZnII ions. The reaction of the chloride salt of the La derivative with di-, tri- and tetrasubstituted benzenecarboxylate ligands has allowed us to isolate 2D and 3D materials. The 3D materials seem to be the first examples of hybrid open frameworks based on Keggin building blocks. The 3D framework built from the connection of ,-Keggin units by trimesate ions exhibits tunnels filled only by water molecules, which can be partly removed and reintroduced at room temperature. Besides these experimental results, simulation has allowed us to generate two virtual hybrid structures derived from those of known silicates by replacing the Si ions by hypothetical ,-Keggin cations and the O -bridging ligands by terephthalate ions, thus showing that 3D frameworks with large pores can be envisioned in the chemistry of hybrid organic,inorganic materials based on ,-Keggin units and motivating further experimental investigations. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source]

Phosphorescent Hybrid Organic,Inorganic Light-Emitting Diodes

ADVANCED MATERIALS, Issue 19 2010
Henk J. Bolink
Competitive efficacy and power conversion efficiency (15,cd,A,1 and above 9,lm,W,1, respectively) are obtained for a hybrid organic,inorganic light-emitting diode (HyLED) with air-stable metal oxides as electrodes. Thanks to the use of a phosphorescent iridium complex and a Cs-doped ZnO cathode, performances approaching those of standard solution-processed organic LEDs can be obtained. [source]

Self-Assembly: Molecular Self-Assembled Monolayers and Multilayers for Organic and Unconventional Inorganic Thin-Film Transistor Applications (Adv. Mater.

ADVANCED MATERIALS, Issue 14-15 2009
15/2009)
A self-assembled monolayer (SAM) of azo stillbazolium sandwiched between two conductive electrodes is shown. The upper and lower electrodes are doped silicon and a Hg drop, respectively, a configuration often used for measuring the conductivity of SAMs and multilayers of hybrid organic and inorganic materials. The evaluation and implementation of these unconventional materials in complex device architectures is highlighted in the review on page 1407 by Sara DiBenedetto et al. [source]

Epoxy,siloxane hybrid coatings by a dual-curing process

ADVANCES IN POLYMER TECHNOLOGY, Issue 2 2009
Giulio Malucelli
Abstract Coatings based on a hybrid organic,inorganic epoxy system were prepared by a dual-curing mechanism, via cationic photopolymerization in the first step at room temperature and a subsequent hydrolysis/condensation reaction of a trialkoxy-silane compound (sol,gel process) at high temperature. To this end, a high Tg epoxy resin (3,4-epoxycyclohexylmethyl-3,-cyclohexenyl-methyl adipate, UVR 6128) was added in increasing amounts to a precursor for the inorganic-like phase (3,4-epoxycyclohexylethyltrimethoxysilane, EETMOS). The mixture contained triphenylsulfoniumhexafluoroantimonate as a cationic photoinitiator. By this method, the strongly acid environment generated by the photolysis of the triarylsolfunium salt in the first step induces the hydrolysis of EETMOS alkoxy-silane groups. The films produced in the first step of the process were thermal treated to promote the condensation reactions of the siloxane moieties. The kinetics of the reactions of photopolymerization and condensation was investigated. It was found that the presence of EETMOS increases both the polymerization rate and the final consumption of epoxy groups. Thermogravimetric analyses performed in air have revealed an increased stability of the hybrid coatings with respect to the films produced from formulations without EETMOS. A significant increase in surface hardness was also observed for the hybrid coatings. The thermo-mechanical properties were found to be strongly affected by the temperature used in the thermally induced reactions in the second step. The hybrid coatings on a low-density polyethylene substrate were found to decrease the diffusivity of oxygen and to increase the oxygen solubility within the coating. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 28:77,85, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20149 [source]

Nanohybrid material of bilateral switch based on diarylethene

JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 11 2007
Ying Zou
Abstract Air-stable hybrid organic,inorganic nanoparticles were prepared, comprising photochromic cationic diarylethene species intercalated in layered MnPS3 by using a microemulsion method. The prepared hybrid material exhibited typical photochromic and fluorescent switch behavior similar to that in solution. Although its response to light was less sensitive, the hybrid material reduced the effect of solvents on its photochromism, and afforded a new approach to the application of molecular switch in solid. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Fast-response organic,inorganic hybrid light-emitting diode

PHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 6 2008
Takeshi Fukuda
Abstract We demonstrated important changes produced on the modulation frequency of hybrid organic,inorganic light-emitting diodes to examine the applicability as a light source for visible optical communications. The fabricated device structure was 4,4,-bis[N -(1-napthyl)- N -phenyl-amino]biphenyl/4,4,-(bis(9-ethyl-3-carbazovinylene)-1,1,-biphenyl:4,4,-bis[9-dicarbazolyl]-2,2,-biphenyl/ZnS/LiF/MgAg. This device showed an improvement in the modulation frequency using ZnS instead of an organic material, tris(8-hydroxyquinoline)aluminum. A maximum cutoff frequency of 20.6 MHz was achieved. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Sodium tris(glycinium) bis(hexafluorosilicate) glycine trisolvate

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2007
Moolya B. Narayana
The title compound, Na+·3C2H6NO2+·2SiF62,·3C2H5NO2, arose from an unexpected reaction of glycine and HF with the glass container. It is an unusual hybrid organic,inorganic network built up from chains of vertex-sharing NaF4O2 and SiF6 octahedra. A pair of glycinium/glycine molecules bridges the chains into a sheet via a centrosymmetric O...H...O link. The other organic species interact with the network by an extensive N,H...F hydrogen-bond network, including bifurcated and trifurcated bonds. Finally, an extremely short C,H...O interaction (H...O = 2.25,Å) is seen in the crystal structure. The Na atom has site symmetry . [source]

Butane-1,4-di­amine zinc(II) hydrogen phosphite

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 12 2004
Lyndsey K. Ritchie
The title compound, poly[zinc(II)-,-butane-1,4-diamine-,-(hydrogen phosphito)] (C4H12N2)0.5[ZnHPO3], is a hybrid organic,inorganic solid built up from 1,4-di­amino­butane mol­ecules, Zn2+ cations (coordinated by three O atoms and one N atom) and HPO32, hydrogen phosphite groups. The organic species bonds to the Zn atom as an unprotonated ligand, resulting in it acting as a bridge between infinite ZnHPO3 layers, which propagate in (100). The complete butane-1,4-diamine species is generated from a H2N(CH2)2, half mol­ecule by inversion symmetry. The zincophosphite sheets contain polyhedral four- and eight-membered rings in a 4.82 topology. [source]