Organic Hybrid Composites Research Articles

Hybrid cobalt phthalocyanine polymer as a potential electrocatalyst for hydrogen evolution reaction

In this work, simple, novel, eco-friendly, low-cost and highly-active cobalt oxytyramine phthalocyanine polymer, poly[CoOTPc] is synthesized and characterized with various spectro-analytical techniques to demonstrate the successful construction of poly[CoOTPc]. In order to enhance the conductivity and electrocatalytic performance of poly[CoOTPc], an organic-hybrid composite with Ketjen-Black (KB) is prepared in different ratios and their activity was assessed towards hydrogen evolution reaction (HER). The linear sweep voltammogram of organic-hybrid composite (3.5:1.5 ratio of polymer to KB) exhibited least overpotential of −79 mV at −10 mA cm−2 current density towards HER in 0.5 M H2SO4 with a Tafel slope closer to the standard catalyst (Pt/C) both in lower and higher overpotentials. In addition, lower charge-transfer resistance is noticed at the hybrid catalyst and is comparable with the standard catalyst suggesting that the designed poly[CoOTPc]+KB organic-hybrid composite is one of the superior, low-cost electrocatalyst towards HER with excellent stability and efficiency for the large-scale integrated green energy systems.

A novel composite of monosodiumtitanate-amidoximatedpolyacrylonitrilefor the sequestration of uranium from contaminated water: An experimental and simulation study

A new inorganic–organic hybrid composite, comprising Monosodiumtitanate(MST) and AmidoximatedPolyacrylonitrile (MPA), has been developed in bead form for the separation of uranium from contaminated water.Inline with the design objectives, asynergistic effect on uranium uptake by MST and Amidoximewas obtained.The measured U uptake capacity is 280 mg/g, the highest ever reported U uptake by any composite in column useable form. U uptake by the composite follows the Langmuir isotherm mechanism. The uptake performance remains unaltered even in the presence of sulphate, nitrate, chloride ion, and carbonate ions. The column performance of the composite was demonstrated by removing U over 12,000-bed volumes of waste effluent from 1000 ppb to down below < 60 ppb level. A mathematicalmodel is developed and used to predict process performance under various operating conditions mimicking scale-up operations with an eye in generating potable water from groundwater.

Study of thermoelectric properties in the PEDOT:PSS/Te double-layer thin film devices

The research on the organic hybrid composites have been regarded as important developing direction in the field of thermoelectric fields, which combine the advantages of organic thermoelectric materials and inorganic thermoelectric materials. In this paper, the thermoelectric properties of Tellurium (Te) and Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) hybrid composite thin film and double-layer structured of PEDOT/Te thin film are studied, separately. We found that the PEDOT:PSS/Te double-layer structured thin film thermoelectric devices can greatly improve conductivity and Seebeck coefficient of PEDOT:PSS compared with the hybrid structure of PEDOT:PSS thermoelectric devices. We thought that the semi-metallicity of PEDOT:PSS and Te forms an ohmic contact interface, which is advantageous to charge transfer, so the double-layer structure of thin film devices possess a better carrier transport channels by the interface effect than hybrid structure devices. On the other hand, the C–V results also confirmed that the interfacial charge accumulation in the PEDOT:PSS/Te double-layered thin-film device, when the temperature rises, the Fermi level close to the conduction band as the temperature increases, leading to the number of high-energy carriers increase at the interface, which effectively improves the Seebeck coefficient of PEDOT:PSS. Our research provide experimental and theoretical support for the development of thin-film thermoelectric materials and devices.

Effect of Hindered Phenol AO‐80 on the Damping Properties for Nitrile‐Butadiene Rubber/Phenolic Resin: Molecular Simulation and Experimental Study

AbstractA combined study of molecular dynamics (MD) simulation, experimental, and linear regression analysis method is presented for hindered phenol of 3,9‐bis[1,1‐dimethyl‐2‐{b‐(3‐tertbutyl‐4‐hydroxy‐5‐methylphenyl)propionyloxy}ethyl]‐2,4,8,10‐tetraoxaspiro‐[5,5]‐undecane (AO‐80)/nitrile‐butadiene rubber/linear phenolic resin (AO‐80/NBR/PR) composites with different AO‐80 contents to quantitatively establish the relations between microstructure and damping performance. The number of hydrogen bonds (NHBs), the fractional free volume (FFV), and the binding energy (Ebinding) of AO‐80/NBR/PR composites with different AO‐80 content are calculated by MD simulation from the microscopic scale. Damping parameters, including the loss factor peak (tan δmax) and the loss peak area (TA) (tan δ &gt; 0.3), are obtained by dynamic mechanical analysis from macroscopic scale. The quantitative relationships between microstructure parameters (NHBs, Ebinding, and FFV) and macroscopic damping properties (tan δmax and TA) are obtained by linear regression analysis. This research is expected to provide a theoretical guidance for improving the damping performance of rubber‐based organic hybrid composites.

Synthesis of mesoporous nickel–titanium-trimesic acid inorganic–organic hybrid composite in ionic liquid microemulsions for adsorption of rhodamine B from aqueous solution

For the first time, mesoporous nickel–titanium-trimesic acid (NTT) inorganic–organic hybrid composite was synthesized in water-in-[Bmim]PF6 ionic liquid microemulsions using the trimesic acid (BTC) as the linker. The synthesized NTT was characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) analysis, powder X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) methods, etc. Then, the isotherm and kinetic of adsorption were studied. The experimental data were well fitted with isotherm models of Langmuir and Freundlich (IMLF) at 298 K and 308 K and better fitted with the isotherm model of Langmuir (IML) at 318 K with the adsorption capacity of 662.212 μmol/g (maximum). The adsorption of rhodamine B (RhB) on NTT can be described by pseudo-second-order (PSO) kinetic model. This proposed method for synthesis of mesoporous NTT inorganic–organic hybrid composite is facile, environment-friendly and operated at room temperature, which could be applied to synthesis of other mesoporous inorganic–organic hybrid composites.

Molecular manganese catalyst anchored on Bi2MoO6 with enhanced photogenerated charges separation for efficient visible-light photoreduction of CO2

Metal–organic hybrid composites are considered stable photocatalysts that exhibit effective CO2 adsorption capability and high charge separation efficiency. Here, the reflux condensation method was used to synthesize organometallic complexes of 2,2-bipyridine-4,4-bisphosphonic acid tricarbonyl manganese bromide (MnP), which were then phosphate anchored onto Bi2MoO6 via a facile self-assembly method. The resulting Bi2MoO6/MnP (150:1) composites catalysts exhibited efficient photocatalytic reduction of CO2 under visible light. The photocatalysts were systematically characterized via XRD, SEM, TEM, BET analysis, FTIR and UV–Vis. Visible light catalytic reduction products were detected qualitatively and quantitatively by ion chromatography and gas chromatography. The results demonstrate that loaded MnP reveal unique C=O, C–C characteristic peak and a peak fluorescence intensity that is less than 50% before loading. Furthermore, a remarkable CO production of turnover number TONCO = 123 and methanol yield of 95 µmol g−1 were obtained at a reaction time of 8 h under optimal conditions. The results due to the MnP in the composites not only enhanced charge carrier extraction but also improved photocatalytic reduction CO2 performance. Overall, the Bi2MoO6/MnP composites exhibit good potential in the photocatalysts fields.

Quantum dot–polymer composites based on nanoporous polypropylene films with different draw ratios

Hybrid composites of polymers with fluorescent nanoparticles are unique materials combining good mechanical properties of the host polymer matrices and luminescent properties of the embedded nanoparticles. Here, we report on the optical characterization of novel inorganic–organic hybrid composites based on nanoporous polypropylene (PP) as a polymer matrix and quantum dots (QDs) as a fluorescent inorganic component. The first type of the composite films is prepared by absorption of CdSe/ZnS QDs onto the porous structure of the PP films, followed by annealing at 170°C, i.e., above the melting point of the PP. The second type of the composite films is obtained by filling of porous QD–PP composites with a nematic liquid crystalline (LC) mixture. Both types of composites are characterized by low light scattering, which makes it possible to study their optical properties by absorbance and fluorescence spectroscopies. TEM and confocal fluorescence microscopy have been used to analyze the aggregation of QDs in composites of different types. It has been shown that introduction of QDs into PP with a low draw ratio decreases the degree of alignment of LC molecules embedded into the pores of QD–PP composite films.

A stable and efficient photocatalytic hydrogen evolution system based on covalently linked silicon-phthalocyanine-graphene with surfactant

A new hybrid silicon-phthalocyanine phenyl covalently functionalized graphene (SiPc(phenyl)2G2) was synthesized. The high fluorescence quenching efficiency and enhanced photocurrent suggested a rapid photoinduced energy transfer from SiPc(phenyl) moiety to graphene sheets through the covalent bond. Using the above synthesized hybrid as a photosensitizer, the SiPc(phenyl)2G2 functionalized Pt nanocomposite (SiPc(phenyl)2G2/Pt) was easily obtained via photodeposition method. The as-prepared SiPc(phenyl)2G2/Pt showed efficient photocatalytic hydrogen generation from water splitting under both UV–vis and visible light irradiation. Interestingly, with the aid of surfactants, the photocatalytic activity and stability of the SiPc(phenyl)2G2/Pt nanocomposites in the solution were distinctly improved owning to the nanocomposite aggregation prevention. This investigation demonstrates a unique approach to construct stable high photoresponisve organic hybrid composites for solar energy utilization.

One-pot synthesis of proton-conductive inorganic–organic hybrid membranes from organoalkoxysilane and phosphonic acid derivatives

Inorganic–organic hybrid membranes consisting of an aliphatic main-chain polymer and Si–O linkages were synthesized via a simple one-pot process from an alkoxysilane derivative, methyl-substituted phenylvinylphosphonic acid, and phosphonic acid acrylate. (Methyldimethoxysilylmethyl)styrene (MDMSMS) was copolymerized with 3-methylphenylvinylphosphonic acid (CH3C6H4VPA, or MPVPA), and 2-hydroxyethyl methacrylate acid phosphate (HEMAP), and then hydrolyzed, yielding inorganic–organic hybrid composites. The formation of the inorganic–organic hybrid structure was confirmed by IR, 13C, and 29Si NMR spectroscopy. The membranes exhibited good thermal stability up to 180°C. The combination of aliphatic chains of the methacrylate derivative and Si–O networks in the hybrid membranes improved the mechanical properties of the membranes, enabling the construction of a membrane electrode assembly. The tensile modulus of the MDMSMS/MPVPA/HEMAP membrane with a composition of 1:1:5 was 688MPa. The conductivity of the 1:1:5 membranes was 4.1×10−2Scm−1 at 130°C and 100% relative humidity (RH), while it was 4.7×10−4Scm−1 at 130°C and 19.3% RH. The peak power of the 1:1:5 membrane was 4.8mW/cm2 at 140°C and 30% RH. The cell utilizing the hybrid membrane was operated at 120°C and 30% RH for 24h without any drop in cell voltage.

Proton-conductive inorganic–organic hybrid membranes synthesized from a trimethoxysilylmethylstyrene–fluorophenylvinyl acid copolymer

Inorganic–organic hybrid membranes composed of Si–O networks and an aliphatic main-chain polymer backbone were synthesized from an alkoxysilane derivative and an F-substituted phenylvinylphosphonic acid via copolymerization and sol–gel reaction. Thus, (trimethoxysilylmethyl)styrene (TMSMS) was copolymerized with 3-fluorophenyl- vinylphosphonic acid (FC6H4VPA), and the product was hydrolyzed to afford an inorganic–organic hybrid composite. Spectroscopic analysis revealed that the inorganic–organic hybrid structure was constructed via the polymerization of TMSMS and FC6H4VPA and the condensation of methoxy-Si bonds. The membranes showed good thermal stability up to 180°C, and it was found that the aliphatic chains bound to the F-substituted aromatic rings and the Si–O linkages in the hybrid membranes improved their mechanical properties. In addition, the proton conductivity of the membranes depended on the P/Si ratio of the product and increased as the P content increased. Notably, the conductivity at 130°C for the hybrid membrane synthesized with a TMSMS/FC6H4VPA ratio of 1/6 was 1.6×10−3Scm−1 and 6.4×10−2Scm−1 at low and 100% relative humidity (RH), respectively, while its power density at 140°C and 30% RH was 3.0mW/cm2.

Damping Properties of Novel Organic Hybrids of Textile Reclaimed Rubber and Hindered Phenol

A series of thin, low-cost and environment-friendly organic hybrid composites consisting of reclaimed rubber (R-Rubber) which is a waste product of roller processing of textile mill filled with organic hindered phenol compound 2, 2-methylenebis (6-tert-butyl-4-methyl-phenol) (AO2246) were fabricated. In this study the damping property of the R-Rubber composites were tested in the dynamic mechanical analysis (DMA). The study concluded that R-Rubber/AO2246 composites exhibited an exceptional damping performance with a broad temperature range. Meanwhile, by addition of AO2246, the tan δ peak maximum (tan δmax) of R-Rubber/AO2246 composite was remarkably increased up to 1.5. Furthermore, with increasing the AO2246 content, storage modulus (E') and loss modulus (E") increases up to R-Rubber/AO2246 (100/80) and then becomes smaller. There is critical value on E and E" increasing which is caused by the excessive crystallization. The Interaction of AO2246 crystallizing, hybridized state and Molecular hydrogen bond led not only to control Tan δmaxof R-Rubber, but also to regulate glass transition temperature and improve the storage modulus, which make R-Rubber have potential applications in fields of engineering.

Thermal properties of carboxylated nitrile rubber/nylon-12 composites-filled lignocellulose materials

Organic hybrid composites based on carboxylated nitrile rubber and nylon-12 reinforced with mercerized and diisocyanated lignocellulose residue (LCR) was prepared. The influence of the LCR on the viscoelastic properties of these organic hybrids was investigated by dynamic mechanical analysis and thermal analysis (differential scanning calorimetry (DSC)). It is found that either the position of the damping peak was shifted to higher values or the intensity of the damping peak was significantly increased with LCR. These results could imply that the LCR enhanced the damping properties of the composites. The thermal stability of the composites was evaluated with the mean values obtained using thermogravimetrical analysis. The decomposition rate was investigated using differential thermal gravimetry. The crystallization behavior of the prepared composites was checked by DSC.

Facile synthesis of SnO2 nanocrystals coated conducting polymer nanowires for enhanced lithium storage

SnO2 nanoparticles uniformly decorated polypyrrole (PPy) nanowires are synthesized by a facile two-step electrochemical reaction method: electropolymerization and electrodeposition. The nanostructured SnO2–PPy hybrids show porous reticular morphology and homogenous distributions. The reticular SnO2–PPy nanowires can increase the electrode/electrolyte interface and accommodate the volume variation of SnO2. When applied as anode materials for lithium ion batteries, the unique nanostructured hybrids deliver meaningfully improved Li+ storage performance with the first reversible capacity of 690 mAh g−1. This facile synthesis procedure can also be simply grafted to other inorganic–organic hybrid composites.

Photoinduced Electron Transfer and Enhancement of Photoconductivity in Silicon Nanoparticles/Perylene Diimide Composites in a Polymer Matrix

An inorganic−organic hybrid composite was prepared from a soluble N-dodecyl-N′-phenyl-3,4,9,10-perylenetetracarboxylic diimide (DOPP) and silicon nanoparticles (NPs). The silicon NPs were synthesized by a solution-phase method. Remarkable photoluminescence (PL) quenching was observed in the composite dispersed in a polymethyl methacrylate matrix. On the basis of the analysis of the PL quenching mechanism, it was demonstrated that a photoinduced electron transfer from silicon NPs to DOPP could occur in the composite. The photoconductivity of the composite was studied, and the photosensitivity enhancement of the composite was realized due to the photoinduced electron transfer between silicon NPs and DOPP.

Colloidal nanocomposite hydrogel particles

Quaternary ammonium salt, (3-acrylamidopropyl)-trimethylammonium chloride was used to synthesize nanohydrogel and composite particles such as inorganic–organic hybrid composites and hydrogel nanoparticles with magnetic properties utilizing a water-in-oil microemulsion system. The positively charged cationic monomer was chosen to promote silica hydrolysis and condensation to prepare silica-hydrogel nanocomposite particles with interesting morphologies. It was shown that highly monodisperse, completely charged nanohydrogel can be used to encapsulate ferrite particles. Furthermore, it was also confirmed that cationic nanohydrogel particles with variant morphology can be prepared by employing suitable silica precursor. Morphology, structure, properties, and size of nanocomposite materials were explored utilizing transmission electron microscopy, atomic force microscopy, and vibrating sample magnetometer.

Inorganic−Organic Hybrid Composites Containing MQ (II−VI) Slabs: A New Class of Nanostructures with Strong Quantum Confinement and Periodic Arrangement

A new class of nanostructures has been prepared and characterized. These nanocomposite hybrid materials are composed of two-dimensional MQ (II−VI) slabs and organic bifunctional molecules that act as links as well as spacers. The most intriguing properties of these nanostructures are that they exhibit strong quantum confinement effect while possessing a perfectly periodic arrangement. The crystal structures of [MnSe(en)0.5] (1; en = ethylenediamine), [MnSe(pda)0.5] (2; pda = propanediamine), [ZnSe(en)0.5] (3), and [ZnSe(pda)0.5] (4) have been analyzed by single crystal and powder X-ray diffraction methods. Compounds 1 and 3 are isostructural and crystallize in orthorhombic crystal system, space group Pbca (No. 61), Z = 4. Crystal data for 1: a = 6.711(1), b = 6.614(1), c = 17.720(4) Å, For 3: a = 6.6326(7), b = 6.4630(6), c = 17.3540(16) Å. Compounds 2 and 4 are isostructural and crystallize in orthorhombic crystal system, space group Cmc21 (No. 36), Z = 4. Crystal data for 2: a = 20.384(4), b = 6.719(1), c = 6.565(1) Å. For 4: a = 19.9731(18), b = 6.6268(7), c = 6.4394(6) Å. The optical absorption experiments show that both 3 and 4 generate a very large blue shift in the absorption edge (1.4−1.5 eV), and both compounds are thermally stable up to 250 °C.

Photogeneration, charge transport, and photoconductivity of a novel PVK/CdS-nanocrystal polymer composite

We report on the photoconductive characteristics of an inorganic:organic hybrid composite in which PVK serves as a polymeric charge-transporting matrix and quantum dots composed of surface passivated cadmium sulfide serve as a charge-generating sensitizer. The PVK:CdS nanocomposites prepared are directly compared with a similar composite composed of PVK and C 60, an extensively studied system due to its promising characteristics. We demonstrate the possibility of tuning the band-gap of these sensitizing nanocrystals through careful discretion in the method of synthesis such that their spectral response can be adjusted to suit a particular wave-length of operation. In this way materials can be fabricated which posses photoconductive characteristics exceeding those observed in the PVK:C 60 system. In this paper results concerning photosensitivity will be presented and the Onsager formalism developed for organic systems will be employed in order to extract the parameters r 0 and Φ 0 from the photocharge generation efficiency data.