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The aim of this study was to demonstrate the influence of laponite smectite clay on the structural properties and release profile of the ureasil-polyether organic-inorganic hybrid nanocomposite. The sol–gel process was used to synthesize the systems combined with the nano-clay, and three concentrations of D-glucose (3, 5, and 10 wt.%) were analyzed for incorporation. The nanocomposite with the most stable D-glucose concentration was used for the release test. The characterization of the laponite colloidal solution was carried out using different viscosity analyses which showed that the 1.5% proportion was the most suitable for formulation due to the formation of a stable gel. The hybrid membrane characterization techniques using infrared spectroscopy and differential thermal analysis show that the formulation components have no chemical or physical incompatibility with D-glucose; the XRD diffractograms confirm that the crystalline domains of D-glucose are suppressed when incorporated into the amorphous Ureasil-polyether material, indicating complete solubilization in the matrix. Finally, the release results show that 20% of the D-glucose was released in 700 min, with a Korsmeyer-Peppas-type kinetic model. Thus, we can conclude that the nanocomposite developed here showed homogeneity and integrity, with satisfactory and adjustable properties such as its mechanical characteristics and the amount of active release, paving the way for its use in various therapies such as bone regeneration. Highlights: The synthesis of ureasil polyether membranes with laponite and D-glucose was carried out in a way that has never been reported in the literature. The application of laponite optimizes its physical properties and the release of D-glucose. Physicochemical tests reveal compatibility between system components. The membranes maintain physical integrity for 9 months without any precipitation. [ABSTRACT FROM AUTHOR]

The article substantiates the possibility of obtaining composite materials with improved functional properties to strengthen the subgrade, containing technogenic soil stabilized by an additive based on a gelling polymer. The introduction of technogenic soils into composites will not only reduce the consumption of expensive materials, but also solve a complex of acute environmental problems. Composite materials can be used in the construction of structural layers of road pavements, foundations of buildings and structures, sites for various purposes, for the prevention and elimination of defects in the foundations of engineering structures during their construction, reconstruction and repair, including in permafrost areas. Stabilized technogenic soils are more durable, frost-resistant and waterproof, which makes them applicable for creating impervious curtains in hydraulic structures and sealing storage facilities for hazardous substances. The cryogenic effect on a composite material allows one to vary its properties within a wide range and modify its macroporous structure. Studying the process of structure formation of the resulting organic-inorganic materials, consisting of macromolecules of high-molecular substances and inorganic inclusions that have undergone cryogenic treatment, will make it possible to specifically regulate their performance characteristics. The best values of strength characteristics were obtained for samples with a stabilizing additive concentration of 100 g/l. The resulting composite materials are hydrophobic, frost-resistant, characterized by a compressive strength of 2.3–6.5 MPa and a thermal conductivity of 0.19–0.20 W/(m·K). Data from differential scanning calorimetry and thermogravimetry and IR spectroscopy revealed that the binding of mineral particles by a stabilizing additive occurs due to the formation of organomineral complexes with the participation of clay minerals and the restructuring of hydration shells. SEM data indicate that crystallinity zones formed due to hydrogen bonds of hydroxyl groups of neighboring polymer chains can participate in the formation of the composite structure. An increase in the number of cryogenic treatment cycles promotes additional structuring and strengthening of the polymer phase due to the formation of additional nodes of the supramolecular network, ordering of crystallinity zones and the appearance of compacted areas in the structure. Computed X-ray tomography revealed an increase in the density of the composite upon drying, which helps to increase its strength characteristics. The structure of the sample is characterized by heterogeneity of the pore space, which is characterized by the presence of both fine-porous and large-porous regions, which determines its thermophysical properties.

1. The crystallographic study displays that the title compound crystallizes in the triclinic system with P −1 space group. 2. The crystal structure can be described as an organic–inorganic (0D) layered perovskite-like structure. 3. The vibrational study at room temperature confirmed the existence of the organic and inorganic functional group. 4. DSC analysis reveals the existence of three reversible phase transitions at T 1 = 345/325 K, T 2 = 483/443 K and T 3 = 496/465 K (heating/cooling) 5. The study of Nyquist plots showed the contribution of grains and grain boundaries in the electrical study, confirming the existence of a non-Debye type relaxation. 6. The AC conductivity shows that the material has the potential of impedance sensors. [Display omitted] In this work, a new Organic-Inorganic chloride (H 3 N–(CH 2) 6 -NH 3)[SnCl 6 ] (1) has been synthesized and characterized by single crystal X-ray diffraction (XRD), IR, Raman and impedance spectroscopies. The crystallographic study displays that the title compound crystallizes in the triclinic system with the P −1 space group. The vibrational study (IR, Raman) at room temperature confirmed the existence of the organic and inorganic functional groups. Differential scanning calorimetry (DSC) analysis reveals the existence of three reversible phase transitions at T 1 = 345/325 K, T 2 = 483/443 K, and T 3 = 496/465 K (Heating/Cooling). Furthermore, the conductivity analysis and the dielectric properties confirm the presence of these phase transitions. AC-conductivity measurement of (1) has been investigated using complex impedance spectroscopy in frequency and temperature range 10 Hz–5 MHz and 313–523 K, respectively. The study of Nyquist plots showed the contribution of grains and grain boundaries in the electrical study, confirming the existence of a non-Debye type relaxation. The AC conductivity shows that the material has the potential of impedance sensors. [ABSTRACT FROM AUTHOR]

The catalytic activity of "pyrrolidine type" fragments included or anchored in the mesoporous silica supports or polymeric frameworks have been fully reported for enantioselective transformation. Nevertheless, low attention was focused on their catalytic abilities to perform base‐catalyzed reaction. Accordingly, hybrid materials including pyrrolidine fragments in the mesoporous silica supports were prepared following different synthesis methods, such as micellar and fluoride sol‐gel routes in absence of structural directing agents. Their great catalytic performance was explored for various base‐catalyzed reactions to the formation of C−C bond through Knoevenagel, Claisen‐Schmidt and Henry condensations under microwave irradiation. The benefits of microwave irradiation combined with suitable catalytic properties of pyrrolidine hybrid materials with strong base sites and high accessibility to active centers, allowed carrying out successfully base‐catalyzed condensation reactions for the production of fine chemicals. Moreover, the hybrid catalyst exhibited high selectivity and good stability over different catalytic cycles contributing to environmental sustainability. [ABSTRACT FROM AUTHOR]

Bioresorbable electronic devices as temporary biomedical implants represent an emerging class of technology relevant to a range of patient conditions currently addressed with technologies that require surgical explantation after a desired period of use. Obtaining reliable performance and favorable degradation behavior demands materials that can serve as biofluid barriers in encapsulating structures that avoid premature degradation of active electronic components. Here, this work presents a materials design that addresses this need, with properties in water impermeability, mechanical flexibility, and processability that are superior to alternatives. The approach uses multilayer assemblies of alternating films of polyanhydride and silicon oxynitride formed by spin-coating and plasma-enhanced chemical vapor deposition , respectively. Experimental and theoretical studies investigate the effects of material composition and multilayer structure on water barrier performance, water distribution, and degradation behavior. Demonstrations with inductor-capacitor circuits, wireless power transfer systems, and wireless optoelectronic devices illustrate the performance of this materials system as a bioresorbable encapsulating structure., (© 2024 The Authors. Advanced Materials published by Wiley‐VCH GmbH.)

According to the intercalation mechanism, an ordered modulation of channel structures of metal oxides is crucial to reversibly accumulate large zinc ions with high surface charge density for improving zinc‐ion battery performance. However, the irreversible structure‐transition commonly results in serious performance decay. Herein, polyanilines are in situ intercalated into the layered vanadium oxide in order to enlarge the lamellar spacing for enhancing the battery performance. With enlarged lattice spacing, the polyaniline intercalated vanadium oxide (PIVO) coupled with a Zn electrode exhibit a large specific capacity of 372 mAh g−1 and good cycling stability. More importantly, in situ characterization results reveal that PIVO allows the accumulation of additional zinc ions without obvious phase transformation and the conjugated polymeric chains enable the structure flexibility in the confined layer space to relieve the intercalation stress for improving cycling stability. Additionally, findings from the in situ infrared spectroscopy measurements elucidate the charge storage mechanism of the battery. Reversible doping processes of polyaniline molecules in vanadium oxide allow the involvement of multiple ions in the charge storage process, improving battery performance. Uncovering the origin of improved charge storage mechanisms is of importance in rationally designing advanced materials with unique organic–inorganic features for high‐performance zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

In this work, a new orthorhombic organic-inorganic hybrid single crystal (C 2 H 10 N 2) 2 MnBr 4.2Br with-Zero-dimensional structure was synthesized by slow evaporation method at 75 °C. The crystal structure and intermolecular interactions were performed by single crystal X-ray diffraction and Hirshfeld surface. Optical properties of (C 2 H 10 N 2) 2 MnBr 4.2Br were systematically studied by Raman, infrared spectrum, UV–vis, photoexcitation spectra, and photoluminescence spectra. The optical band gap (E g = 2.61 eV) were calculated from the absorption spectra of (C 2 H 10 N 2) 2 MnBr 4.2Br. This hybrid materials also had shown good thermal stability (decomposition temperature: 288–660 °C). Finally, photoluminescence measurements showed a strong excitation line at 362 nm and a strong fluorescence at 537 nm which makes it a promising material in luminescence field. [ABSTRACT FROM AUTHOR]

A top‐down approach is applied for the production of polyurethane (PU)–polyhedral oligomeric silsesquioxane (POSS) nanocomposites, namely melt blending. As opposed to the typical chemical incorporation during synthesis, a POSS moiety with two hydroxyl groups is melt blended into a commercial thermoplastic polyurethane with mass fraction up to 2 wt %. POSS disperses in the matrix in submicrometer‐sized crystals, as well as in length scale of few tens of nanometers, in the bulk. Phase separation of the produced composites was studied by both standard dynamic and isothermal annealing experiments. In an approach rare in the literature, the dynamics of phase separation is discussed based on isothermal differential scanning calorimetry curves recorded during annealing. The blended‐in nanoparticles affect the micromorphology in a complicated manner, dependent on the intrinsically complex phase separation mechanism of PU. At higher temperatures, POSS slows down the phase separation, whereas at lower ones, it enhances and accelerates it. POSS decreases the mechanical modulus of the final material, presumably as a result of changes in the microphase separation. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 1133–1142 [ABSTRACT FROM AUTHOR]

Chitosan/silica nanocomposite membrane doped with Al2O3 nanoparticles is prepared via sol–gel route by mixing the inorganic silica-based in the chitosan matrix. Understanding the interaction between chitosan molecules as a natural biopolymer and aluminosilicate as a semiconductor is one of the principal objectives for the development of new environmentally benign strategies for the synthesis of low-cost organic-inorganic nanocomposites membranes. The obtained nanocomposite membranes are investigated by X-ray diffraction (XRD), high resolution-scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The optical and antimicrobial properties of the prepared nanocomposite membranes were investigated. The obtained results clarified that chitosan/aluminosilicate nanocomposite membranes were considered as a good candidate for spectroscopic and biological applications. [ABSTRACT FROM AUTHOR]

Abstract In this study, the kraft lignin/cubic boron nitride hybrid materials have been obtained and characterized for the first time. The effectiveness of the combination of lignin and boron nitride was evaluated on the basis of Fourier transform infrared spectroscopy. Furthermore, it was confirmed that the addition of cubic boron nitride (cBN) improved the thermal stability of the inorganic-organic material. Upswing in thermal properties allowed to apply the prepared materials in preparation of model abrasive composites. Beneficial influence of the lignin/cBN filler was also proven by a noticeable decrease in the amount of harmful phenol released from the compositions during headspace gas chromatography analysis. Mechanical properties of the lignin/boron nitride hybrids and resin systems were investigated by the three-point flexural test. The obtained results show that the used additives can be promising materials for abrasive tools combining the good properties of lignin as a plasticizer and of cubic boron nitride as a filler which improves the thermal and mechanical properties of finished products and, at the same time, limits the negative impact on human health and environment. [ABSTRACT FROM AUTHOR]

For the first time, a series of catechol-containing Schiff bases, tetrasubstituted at the lower rim thiacalix[4]arene derivatives in three stereoisomeric forms, cone, partial cone, and 1,3-alternate, were synthesized. The structure of the obtained compounds was proved by modern physical methods, such as NMR, IR spectroscopy, and HRMS. Selective recognition (Kb difference by three orders of magnitude) of copper (II) cation in the series of d-metal cations (Cu2+, Ni2+, Co2+, Zn2+) was shown by UV-vis spectroscopy. Copper (II) ions are coordinated at the nitrogen atom of the imine group and the nearest oxygen atom of the catechol fragment in the thiacalixarene derivatives. High thermal stable organic-inorganic copper-based materials were obtained on the base of 1,3-alternate + Cu (II) complexes.

Abstract In this work, for the first time, we describe the design and synthesis of novel fluorinated poly(arylene ether)/silica cross-linked materials (FPAE/SiO 1.5) through a sol-gel process by using the triethoxysilyl-containing fluorinated polyethers as precursors for both organic and inorganic networks formation. The polyether-based precursors with the sol-gel active species were synthesized via hydrosilylation reaction between triethoxysilane and the corresponding allyl-functionalized FPAE under Pt catalysis. Herein, we present two approaches of hydrolysis triethoxysilane groups to silanol ones within sol-gel chemistry: (1) hydrolysis with air moisture and (2) hydrolysis of the ethoxysilyl groups at the interface between two liquids. The mechanical and thermal properties of the FPAE/SiO 1.5 materials were studied depending on the structure of macromolecular chains and synthetic route. Scanning electron and atomic force microscopies were employed to investigate the morphology of the resulting silica-containing cross-linked materials. The resulting FPAE/SiO 1.5 films were flexible and tough with tensile strength above 25 МPа, and exhibited high thermal stability, having the initial decomposition temperature about 300°С. For more detailed explanation of the thermophysical behavior of the FPAE/SiO 1.5 materials, the synthesis method of new silica-containing organic-inorganic system was developed by the direct hydrosilylation reaction between allyl-functionalized polyethers and 1,1,3,3-tetramethyldisiloxane. All films exhibited high hydrophobic properties (water contact angles above 102°), low dielectric constants and losses at room temperature. In particular, the FPAE/SiO 1.5 film prepared from tetrafluorobenzene-based polyether showed the ultra-low dielectric constant of 1.86 at 10 kHz. This makes the obtained polymer FPAE/SiO 1.5 materials attractive for microelectronics and many other emerging applications. Graphical abstract Image 1 Highlights • Novel fluorinated poly(arylene ether)/silica-based materials are prepared through a sol-gel process. • Two approaches of hydrolysis triethoxysilane groups to silanol ones within sol-gel chemistry are developed. • New silica-containing organic-inorganic system by the direct hydrosilylation reaction are synthesized. • The polymers exhibit excellent thermal and mechanical stability, high hydrophobicity, and low dielectric constants. [ABSTRACT FROM AUTHOR]

Clay has been widely used since Antiquity. However, its application remains limited due to its low dispersion in water. In this review paper, we introduce amino organophyllosilicates (hereafter: aminoclays), which are synthesized by metal salt and organotrialkoxylane at room temperature. Such organic-inorganic materials have been applied in different areas. There is also the strategy of incorporating aminoclays with another material in order to expand its potential. However, the cytotoxicity of some aminoclays toward mammalian cells has to be reduced before application in practical fields. By evaluating the latest research papers, we take a closer look at the applications of various aminoclays in biological as well as environmental fields. [ABSTRACT FROM AUTHOR]

Abstract: This study reports the development of a functional adsorbent synthesized by the molecular imprinting method in a sol–gel matrix. The adsorption capacity of the organic-inorganic hybrid adsorbent material was tested on tannin compounds, i.e., phenolic substances that are among the most difficult compounds to remove in industrial wastewater. The specific surface area obtained by nitrogen porosimetry analysis was between 2 and 579 m2 g−1 due to each sol–gel synthetic route used. Small-angle X-ray scattering analysis revealed that the hybrid silicas were arranged in a multi-level structure consisting of three levels of organization and a surface fractal structure. Diffuse reflectance spectroscopy revealed the interactions between the tannins and the silica matrix, and confirmed the partial removal of tannins after ultrasound-assisted extraction. Zeta potential analysis showed that the values ranged between −37.9 and +27.8 mV, where non-functionalized xerogels were anionic and those functionalized with organosilane were cationic. The structural and textural characteristics of the hybrid materials were found to depend on the sol–gel synthetic route, which in turn affected the adsorption capacity. The adsorbent functionalized with (3-Aminopropyl) triethoxysilane was an effective adsorbent for the tannin compounds tested here, with approximately 90% removal in aqueous solutions.Graphical abstract: [ABSTRACT FROM AUTHOR]

Single crystals of an organic-inorganic hybrid (C 2 H 5 -C 6 H 4 -NH 2 ) 2 ZnBr 2 have been grown by the slow-diffusion method and characterized by Single-Crystal X-Ray Diffraction (SC-XRD) at 295 K. This compound crystallizes in the monoclinic system, with the space group C 2/ c and the following cell parameters: a = 32.336 (3) Å, b = 4.8539 (4) Å, c = 12.2334 (9) Å, β = 97.019 (5)°, V = 1905.7(3) Å 3 and Z′ = 4. The crystal packing is based on well-ordered alternating ZnBr 2 inorganic layers and C 2 H 5 -C 6 H 4 -NH 2 organic layers. The crystal structure has been analyzed and discussed in terms of molecular geometry as well as intra and intermolecular interactions. Comparisons with some homologues materials of general formula (R-NH 2 ) 2 ZnX 2 (X = Cl, Br), (R = C 2 H 5 -C 6 H 4 , C 6 H 5 ) are also done. [ABSTRACT FROM AUTHOR]

This study, it was aimed to examine the change in the antimicrobial effect of sea anemone Parazoanthus axinellae extract by forming its nanoflowers. A scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX) were expended to observe the morphologies of the Cu NFs that had been produced. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were expended to analyze the managing assemblies in P. axinellae extract, which perform an effective part in the synthesis routine, as well as the crystal assembly of NFs. P. axinellae extract mediated the HNFs (Hybrid nanoflowers) are at high, pure crystalline nature, flower shape with a crystallographic system at the nanoscale with mean crystallite size 21.9 nm using XRD, and average particle size ~10 nm by SEM. The broad absorption band at 2981-2915 cm -1 in the FT-IR spectra of anemone extract and Cu-anemone NFs represents the unique peak of hydroxy groups. In addition, Cu NFs were tested for their antibacterial properties. Cu NFs have been discovered to exhibit antibacterial properties. It is suggested that P. axinellae extract and various inorganic components be used to synthesize a variety of NFs and assess their suitability for usage in biomedical fields., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

This review deals with silica based hybrid materials obtained by the sol-gel method. It involves concepts, classifications and important definitions regarding the sol-gel method that allows obtaining materials with organic and inorganic components dispersed in a molecular or nanometric level. We discuss the properties and characteristics of hybrid materials related to experimental synthesis conditions. We devote a special attention to the nanostructured materials, where the self-organization is imposed by the organic component. Finally, we present some important applications of these materials based on their specific properties.

A new family of stable layered organic-inorganic materials has been prepared, in one-step solvothermal process. They are based on an ordered nickel cluster-type nanoribbons separated from each other by specific alkyl (heptyl- or dodecyl-) arylic mono-carboxylate moieties acting as molecular spacers, perpendicular to the 1D inorganic chains. These organic spacers contain hydrocarbon tails with different length which control the separation level between inorganic 1D sub-units, inhibiting the 3D growth of conventional DUT-8-type metal-organic frameworks (MOFs). The lamellar nature of the materials formed was studied and confirmed by different characterization techniques, showing the structural location of individual organic and inorganic building units. They have been successfully used as a long-lasting biodegradable and water-proof materials for controlled release of chemicals, such as pheromones for sustainable treatment of insect plagues. [ABSTRACT FROM AUTHOR]

This is a review of hybrid materials based on silica as an inorganic phase used as drug delivery systems (DDS). Silica based DDS have shown effectivity when compared with traditional delivery systems. They present advantages such as: (a) ability to maintain the therapeutic range with minor variations; (b) prevention of local and systemic toxic effects; (c) plasma concentrations increase of substances with a short half-life; and (d) reduction of the number of daily doses, which may increase patient adherence to the treatment. These advantages occur due to the physical, chemical and optical properties of these materials. Therefore, we discuss the properties and characteristics of them and we present some applications, using different approaches of DDS to ensure therapeutic effectiveness and side effects reduction such as implantable biomaterial, film-forming materials, stimuli-responsive systems and others. [ABSTRACT FROM AUTHOR]

A simple procedure was developed for the synthesis of sulphonic group-functionalised silica material (SAM) under formic acid conditions without the presence of surfactant species or precursors. The organic–inorganic hybrid materials exhibited high catalytic activity and excellent thermal stability in the alkylation of aromatics with olefins. Pyridine-FTIR indicated that SAM has abundant Lewis acid sites, especially weak acid sites. 29 Si and 27 Al MAS NMR confirmed that aluminium methanesulphonate was anchored on the surface of the silica matrix by the covalent bond of Si–O–Al. [ABSTRACT FROM AUTHOR]

Urethane methacrylate trimethoxysilane (UAMS) organic–inorganic material was synthesized by the reaction of isophorone diisocyanate with hydroxyethyl methacrylate and aminopropyltrimethoxysilane. This precursor was then added to urethane trimethacrylate (UTMA); consequently, silica domains were appeared within the resulting ultraviolet (UV)-irradiated hybrid coatings. The sol–gel precursors having different amounts of UAMS as well as the UV-irradiated nanocomposite specimens were thoroughly characterized by FTIR, 1 H NMR, 13 C NMR, SEM, and TGA. The results provided support for the fact that thermo-mechanical properties of hybrid coatings were enhanced markedly by the incorporation of UAMS. This can be explained by the generation of Si–O–Si hard segments throughout the UV-cured films. Study on hardness and thermal stability behavior provided further evidences for the action of UAMS as coupling agent. Noticeably, thermal stability of hybrid coatings experienced an upward trend with the UAMS content, which can be inferred on the basis of strict restrictions on the mobility of polymer chains imposed by the crosslinked network. [ABSTRACT FROM AUTHOR]

A novel strategy for fabrication of ordered ceramic-metal nanocomposites was demonstrated by multifunctional block copolymer/metal nanoparticle self-assembly. Hybrid organic-inorganic block copolymer poly(3-methacryloxypropyl-T8-heptaisobutyl-polyhedral oligomeric silsesquioxane- block- N, N-dimethylaminoethyl methacrylate) was synthesized and used as a bi-functional structure directing agent for ligand-stabilized platinum nanoparticles to form ordered organic-inorganic nanocomposites with dense loading of inorganic species in both microphase separated domains. Subsequently, thin films of the hybrid material were converted to ordered silica (ceramic)-platinum (metal) nanocomposites via UV-assisted ozonolysis. This is the first time ordered ceramic-metal nanocomposites were achieved through a bottom-up approach, opening up opportunities for the design and synthesis of a broad range of ordered inorganic-inorganic nanocomposites. [ABSTRACT FROM AUTHOR]

Expanding interspace and introducing vacancies are desired to promote the mobility of Zn ions and unlock the inactive sites of layered cathodes. However, this two-point modulation has not yet been achieved simultaneously in vanadium phosphate. Here, a strategy is proposed for fabricating an alcohol-based organic-inorganic hybrid material, VO 1- x PO 4 ·0.56C 6 H 14 O 4 , to realize the conjoint modulation of the d-interspace and oxygen vacancies. Peculiar triglycol molecules with an inclined orientation in the interlayer also boost the improvement in the conversion rate of V 5+ to V 4+ and the intensity of the PO bond. Their synergism can ensure steerable adjustment for intercalation kinetics and electron transport, as well as realize high chemical reactivity and redox-center optimization, leading to at least 200% increase in capacity. Using a water-organic electrolyte, the designed Zn-ion batteries with an ultrahigh-rate profile deliver a long-term durability (fivefold greater than pristine material) and an excellent energy density of ≈142 Wh kg -1 (including masses of cathode and anode), thereby substantially outstripping most of the recently reported state-of-the-art zinc-ion batteries. This work proves the feasibility to realize the two-point modulation by using organic intercalants for exploiting high-performance new 2D materials., (© 2022 Wiley-VCH GmbH.)

A record power conversion efficiency of 12.2% is achieved for a hybrid organic‐inorganic Schottky solar cell using a simple and low temperature (<150 °C) process. The heterojunction diode based on a simple integration of organic thin layers and silicon promises a low cost way to fabricate high performance solar cells. [ABSTRACT FROM AUTHOR]

Abstract: This work investigates the mechanical properties of different scratch resistant coatings, namely, a mixture of 3-glycidoxypropyltrimethoxysilane (GPTMS) with either colloidal silica particles or tetraethoxysilane (TEOS). Coatings were prepared by the hydrolysis and the condensation of the precursor''s alkoxide (sol–gel process) with thermally catalyzed polymerization of epoxy ring of GPTMS. Dip deposition techniques were used on silicon substrate. The nanoindentation technique was used to analyze the force required to indent the coating with a diamond tip. At low forces, this technique, based on indentation depth, predicts the hardness and the elastic modulus of the coating, while at higher forces, cracks appear. Another analysis based on geometric approach, namely, the crack length, allows the determination of both coating and interface toughness. [Copyright &y& Elsevier]

Organic/inorganic hybrid networks were prepared by a novel solvent-free two-step synthesis method. In the first step, prehydrolyzed-condensed reactive inorganic precursors (clusters) were prepared by a sol-gel process from monomeric alkoxysilanes with amino and glycido groups. The second step comprised their addition into epoxy resin and amine hardener, followed by the reaction of all components giving the final hybrid crosslinked materials. Their structure was evaluated by small-angle X-ray scattering, transmission electron microscopy, scanning electron microscopy, and dynamic mechanical and thermal analysis. The morphology of the organic/inorganic hybrid structures formed from glycidoprecursor revealed spherical silica-rich domains forming agglomerates with diameter from 100 to 500 nm. The aminoprecursor led to large highly condensed and branched silicon-rich structures. The organic/inorganic hybrid networks obtained from this precursor consisted of mixed silicon-organic phases covalently interconnected via epoxy-amine bonds. Such hybrid networks showed significantly improved thermomechanical properties and better resistance against thermooxidation when compared with the neat epoxy-amine network. Thin films as well as bulk materials were successfully prepared by this process. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid materials suitable for the development of sol-gel coatings for metallic surfaces were prepared by hydrolysis and condensation of γ-methacryloxypropyltrimethoxysilane (MAPTMS) and tetramethyl orthosilicate (TMOS). The hydrolysis of MAPTMS/TMOS was carried out in an ethanol/water solution. The prehydrolysis stage of MAPTMS/TMOS system was monitored by Fourier transform infrared spectroscopy (FTIR) and liquid-state Si and C nuclear magnetic resonance (Si and C NMR). FTIR analysis indicated that the hydrolysis of MAPTMS/TMOS was accomplished as far as the (SiOMe) band corresponding to unhydrolyzed silane disappeared. The concentration of the alkoxy groups and the extent of self-condensation of mono-, di-, and trisubstituted siloxanes (T species) in the sol were estimated by using liquid-state Si NMR spectroscopy. The hydrolysis of the prepared sol was also evaluated by liquid-state C NMR spectroscopy. The results indicated that under the adopted synthesis strategy conditions, the hydrolysis process requires 4 h to be completed. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid thin films have been prepared by a modified sol-gel route using tetraethyl orthosilicate as the inorganic (silica) source, methyl methacrylate (MMA) as the organic source, and 3-trimetoxysilylpropyl methacrylate as the coupling agent. The films were prepared by spin coating on Si (100) p-type substrates and subsequently heat-treated at 90 °C. Fourier transform infrared results reveal a set of absorption bands associated with the formation of both PMMA and SiO phases in the hybrid films. Capacitance-voltage ( C- V) characterization was carried out on metal-insulator-metal (MIM) and metal-insulator-semiconductor (MIS) structures, with the hybrid films as the insulator layer to evaluate the electrical properties. We present a detailed comparative analysis of the dielectric constant obtained from C- V characterization in the frequency range of 1 kHz-1 MHz. For the PMMA-SiO hybrid material the dielectric constant values obtained were around 9.5 at 1 MHz which is superior to the values reported for thermally grown SiO and pure PMMA materials. The interface state density for PMMA-SiO on Si was approximately 10 cm, which is comparable to the standard SiO/Si structures. Due to the electrical behavior and low processing temperatures this hybrid dielectric is a very promising candidate for flexible electronic devices and its subsequent implementation does not require complex equipment. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of polyphenylethynyl diphosphonic acids was accomplished as well as their incorporation to γ-ZrP by topotactic phosphate/phosphonate partial exchange. The materials, characterized by solid-state NMR, XRD, elemental analysis and molecular modelling, bore truly pillared structures with a high degree of ultramicroporosity. The remaining surface phosphates from the partial phosphate/phosphonate replacement were further exchanged with methylphosphonate, phosphite or hypophosphate leading to a library of new materials that retained the pillared ultramicroporous structure. The porous solids displayed reasonable capacities to store hydrogen by physisorption. [ABSTRACT FROM AUTHOR]

Abstract: The preparation of organic–inorganic materials based on the topotactic exchange reactions of the γ phase of zirconium phosphate and polyphenyl bisphosphonates is reported. The treatment of these materials with hypophosphoric, phosphorous and methylphosphonic acids easily led to an isomerization of the γ phases to their α allotropes. These reactions rendered finely engineered supramolecular structures by means of mild, simple processes performed in the solid–liquid interface. This kind of clean γ-to-α transformations described in our work has few precedents in the literature and allows for the effortless preparation of libraries of similar materials in which the testing of a given set of properties versus subtle structural changes may be easily performed. Using this rationale we have produced materials able to store up to 1.7% (w/w) of H2 at 77K and 1atm with such high ultramicroporosity that the DOE-goal H2 densities established for 2010 could be complied at pressures well below 5atm. [Copyright &y& Elsevier]

Abstract: To obtain excellent thermal stability, a series of dendronized organic–inorganic hybrids were synthesized and characterized. Dendronized alkoxysilane dyes were prepared via the ring opening addition reaction of azetidine-2,4-dione of chromophore-containing dendrons, with 3-aminopropyltriethoxysilane. Subsequently, the precursor, dendronized alkoxysilane dyes could be hydrolyzed and copolymerized with phenyltriethoxysilane (PTEOS) with the weight ratios of 1:1, 1:3, 1:5 and 1:7 in the presence of water and formic acid. After curing and poling process, organic–inorganic hybrid thin films with homogeneous morphology were obtained. Electro-optical (EO) coefficients (r 33) of 2.9–13.0pm/V were achieved. Due to the site-isolation effect, the sample with high generation dendrons possessed a higher EO coefficient/dye content ratio. In addition, because of the improved miscibility between organic and inorganic segments due to highly branched hydrogen bonding-rich dendrons, NLO polymers with waveguide properties ranging from 3.2 to 4.2dB/cm at 1310nm were obtained. These dendronized organic–inorganic NLO hybrids also show greatly enhanced temporal stability at 100°C. [Copyright &y& Elsevier]

In the field of commercialization, organic–inorganic hybrid perovskite materials are becoming more popular these days in view of their prospective use in solar cells and also in other optoelectronic applications. In this paper, a non-toxic CH 3 NH 3 CuCl 3 (MACuCl 3) hybrid perovskite is successfully synthesized via the slow evaporation solution growth technique. The monoclinic phase of the material is checked using the X-ray diffraction measurement. The chemical composition of the prepared compound is discussed by a scanning transmission electron microscope coupled with the energy dispersive X-ray spectroscopy (STEM-EDS). Such systematic characterizations as differential scanning calorimetry (DSC) measurements and dielectric measurements indicate that MACuCl 3 goes through a reversible phase transition at T 1 ≈ 350/352 K MACuCl 3 demonstrates a semiconducting property with a direct band gap value of approximately 2.54 eV. Over the 10−1-106 Hz frequency range, the dielectric constant, the loss factor, the electric modulus and also the electrical conductivity of MACuCl 3 show strong temperature dependence. The Nyquist plot confirms the various contributions of grains and grain boundaries to the total impedance. In the high-frequency region, the dielectric constant tends to increase with temperature. The modified Cole–Cole plot asserts that while the relaxation time decreases with the rise in temperature, the space charge and free charge conductivity increase the moment the temperature climbs. In accordance with the modified Kohlrausch-Williams-Watts (KWW) equation, an asymmetrical nature corresponding to the non-Debye type of the perovskite is noticed in the electric modulus spectra at different temperatures. Moreover, the imaginary part of the electric modulus spectra is found to shift from the non-Debye toward the Debye type with the increase in temperature despite not getting the exact Debye response and emerging as a semi-conductor material. The study of the charge transfer mechanism of MACuCl 3 is carried out based on Elliott's theory. The conduction mechanism in MACuCl 3 is interpreted through the following two approaches: the overlapping large polaron tunneling (O L P T) model (phase 1) and the non-overlapping small polaron tunneling (N S P T) model (phase 2). Moreover, the high dielectric constant of MACuCl 3 which is associated with a low dielectric loss makes it a possible candidate for energy harvesting devices. • The CH 3 NH 3 CuCl 3 compound crystallized in monoclinic phase with the P2 1 /n space group. • A phase transition at 350 K has been assured by DSC measurements and demonstrated by the study of the dielectric properties. • CH 3 NH 3 CuCl 3 demonstrates a semiconducting property with a direct band gap value of approximately 2.54 eV. • The conduction mechanism which was interpreted by several models on the basis of Elliott's theory might be assigned in phase 1 to the overlapping large polaron tunneling (OLPT) model and to the non-overlapping small polaron tunneling (NSPT) model in phase 2. [ABSTRACT FROM AUTHOR]

Mauritz et al. exploited the polar/nonpolar nanophase-separated morphologies of Nafion® perfluorosulfonic acid membranes, as well as a chemically modified Nafion® precursor film, as interactive templates capable of directing sol-gel hydrolysis→condensation polymerizations of inorganic alkoxides and organoalkoxysilanes and the geometrical distribution of inorganic oxide or organically modified silicate nanophases that result upon drying. This paper reviews our studies involving Nafion® in situ sol-gel reactions of alkoxides of silicon, titanium, aluminum, zirconium, and organoalkoxysilanes and combinations of these monomers. Also discussed are similar studies by other investigators. We discuss spectroscopic, microscopic, x-ray scattering, thermal, mechanical tensile, dynamic mechanical, dielectric relaxation, and gas permeation tools that were employed to interrogate the structures and properties of these heterogeneous materials over a range of dimensional scales. Methods of tailoring the energetic environment, or polarity, within the cluster domains by insertion of inorganic oxide or organically-modified silicate nanostructures are presented. Finally, we discuss the potential for these nanocomposite membranes within a number of areas including gas and liquid separations technology, catalysis, and proton exchange membranes for fuel cell technology. [ABSTRACT FROM AUTHOR]