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General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Composé de métal de transition, Transition element compounds, Adhérence, Adhesion, Adherencia, Bactéricidie, Bactericidal effect, Bactericidia, Caractérisation, Characterization, Caracterización, Couche mince, Thin film, Capa fina, Effet solvant, Solvent effect, Efecto solvente, Film, Película, Nanostructure, Nanoestructura, Oxyde de nickel, Nickel oxide, Níquel óxido, Procédé sol gel, Sol gel process, Procedimiento sol gel, Préparation, Preparation, Preparación, Anitibacterial activity, NiO, Sol-gel preparation, and Structural characterization

This study presents the characterization and antibacterial activity of nanostructure NiO films synthesized by sol-gel dip coating method using solvents of different polarities and viscosities without any catalysts, templates or surfactants. Methanol, 1,4-butanediol, ethanol, and 2-propanol were used as solvent. The antibacterial activity was tested against two common foodborne pathogenic bacteria Staphylococcus aureus (ATCC 25922) and Escherichia coli (ATCC 29213) using the so-called antibacterial drop test. X-ray diffraction, scanning electron microscopy, atomic force microscopy, UV-vis spectroscopy and static contact angles test were used to analysis the structure and morphology character, surface topography, optical property and surface wettability of different coatings, respectively. The characterization results showed different preferred crystallographic orientations, particle sizes, surface properties and optical band gap of NiO films according to the solvent physicochemical properties. The antibacterial efficiencies were affected by the physiological status of the bacterial cells and degree of bacteria adherence, morphologies and crystal growth habits, surface and optical properties of NiO samples.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Agent surface, Surfactant, Agente superficie, Alumine, Alumina, Alúmina, Matériau poreux, Porous material, Material poroso, Mésoporosité, Mesoporosity, Mesoporosidad, Procédé sol gel, Sol gel process, Procedimiento sol gel, Rétraction, Retraction, Retracción, Structure, Estructura, Agent structurant, Template, Al2O3, Dual soft templates, Gel retraction, Porous alumina structures, Sol-gel, and Surfactants

This work presents a method that enables the synthesis of porous alumina in the presence of different types of surfactant. The method is based on a sol―gel transition, using surfactants and droplets of a nonpolar phase as templates. The main purpose was to establish a relationship between the templates and the resulting pore structure. The results show that depending on the type of surfactant used (ionic or nonionic), materials presenting variations in the pore family distribution, X-ray powder diffraction patterns and sample morphology were formed. During the synthesis of these alumina samples, the drying step caused loss of the porous structures, so the shrinkage due to different types of surfactants was evaluated.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Théorie des réactions, cinétique générale. Catalyse. Nomenclature, documentation chimique, informatique chimique, Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry, Catalyse, Catalysis, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Matériau poreux, Porous material, Material poroso, Acide, Acids, Acido, Aérogel, Aerogel, Aerógel, Carbure, Carbides, Carburo, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Catalyseur, Catalyst, Catalizador, Composé de métal de transition, Transition element compounds, Etude comparative, Comparative study, Estudio comparativo, Procédé sol gel, Sol gel process, Procedimiento sol gel, Réaction catalytique, Catalytic reaction, Reacción catalítica, Xérogel, Xerogel, Zircone, Zirconia, Zircona, ZrO2, Carbide, and Heteropolytungstic acid

Zirconia doped by heteropolytungstic acid HPW have been synthesized by sol―gel method using two drying techniques of the solvent evacuation. Samples were analyzed with adsorption―desorption of N2 at 77 K, and the aerogel catalyst was found to exhibit a higher surface area and a higher average pore diameter compared to xerogel. XRD results show that aerogel develops ZrO2 tetragonal phase, whereas xerogel is amorphous. The thermal analysis studies show that the aerogel's thermal stability is better than the xerogel one. The catalytic behavior of the aerogel and xerogel toward the nature of the isomerization products probably depends on the acidity and the presence of carbide species. This has been explained by XPS and isopropanol dehydration reaction. In fact, the deconvolution aerogel's Cls bands reveals the presence of four carbon species assigned to C―C, C=O, C―O and carbide species.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Sciences appliquees, Applied sciences, Energie, Energy, Energie naturelle, Natural energy, Energie solaire, Solar energy, Conversion photovoltaïque, Photovoltaic conversion, Cellules solaires. Cellules photoélectrochimiques, Solar cells. Photoelectrochemical cells, Cellule solaire, Solar cell, Célula solar, Composé de métal de transition, Transition element compounds, Nanofil, Nanowires, Nanotube, Nanotubo, Procédé sol gel, Sol gel process, Procedimiento sol gel, Pyrite, Pirita, Rayonnement solaire, Solar radiation, Radiación solar, Sulfure de fer, Iron sulfide, Hierro sulfuro, Synthèse, Synthesis, Síntesis, Agent structurant, Template, Band gaps, FeS2, and Sol―gel

Highly ordered iron pyrite (FeS2) nanowires and nanotubes arrays have been fabricated by using sol―gel method with AAO templates. The prepared nanowires and nanotubes have uniform lengths and 200 nm diameters. Their crystal phase was identified as cubic FeS2 by using X-ray diffraction, Raman spectroscopy, high-resolution transmission electron microscopy and selected-area electron diffraction pattern. The direct optical band gaps of the as-prepared FeS2 nanowires were 0.98 and 1.23 eV, respectively, indicating their suitability for photovoltaic application.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Métal transition, Transition metal, Metal transición, Basse température, Low temperature, Baja temperatura, Nanopoudre, Nanopowder, Nanopolvo, Poudre, Powder, Polvo, Procédé sol gel, Sol gel process, Procedimiento sol gel, Synthèse, Synthesis, Síntesis, Technologie, Technology, Tecnología, Zirconium, Zirconio, Nano-powders, Novel complex, Sol-gel, and ZrB2

Zirconium diboride nano-powders were synthesized by novel complex sol-gel technology at low temperature. Zirconium oxychloride as source of zirconium was complexed via adding propylene oxide that could form the stable zirconium sol by protonation and ring-opening reactions and boric acid as source of boron was dissolved effectively using glycerol that acted as complexing agent to create the boron network through forming stable coordination compound. Additionally, glycerol could be carbonized as source of carbon, which could replace the conventional carbon source additives. Then the mixed sols were gelated, dried, and exposed to 1,450 °C for 2 h with flowing argon in the furnace. High purity of ZrB2 nano-powders with spherical shape of ca. 200 nm were synthesized via carbothermal reduction. The mechanism of two complexing agents were discussed combining with the infrared spectroscopy analysis results, and the powder characteristics were performed by using X-ray diffraction and transmission electron microscopy.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Composé de métal de transition, Transition element compounds, Céramique, Ceramic materials, Cerámica, Poudre, Powder, Polvo, Procédé sol gel, Sol gel process, Procedimiento sol gel, Stabilité thermique, Thermal stability, Estabilidad térmica, Synthèse, Synthesis, Síntesis, Texture, Textura, Yttrium Silicate, Yttrium Silicates, Ytrio Silicato, Ceramics, Sol-gel method, Texture properties, and Yttrium disilicate

Stoichiometric compounds Y2Si2O7 were synthesised by an intensified sonohydrolysis-condensation reaction using hydrate yttrium nitrate and tetraethyl orthosilicate as starting materials. The resulting powders were characterized by means of thermo gravimetric-differential thermal analysis, high temperature X-ray diffraction, electron probe microanalysis, scanning electron microscopy, laser scattering particle size analyzer, N2 adsorption-desorption isotherms measurements and specific surface area analysis. We found that the phase formation and texture were very dependent on the sol-gel process parameters such as starting compounds, catalyst, water content, molar ratios of Y3+/Si4+ and other experiment conditions. The combined effects of polyethylene glycol and acetic acid on the prepared powders have been discussed. The investigation on thermal stability of the obtained disilicate is also presented for potential high temperature membrane or thermal barrier/ environmental barrier coating application.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Composé binaire, Binary compound, Compuesto binario, Modification, Modificación, Nanoparticule, Nanoparticle, Nanopartícula, Nanosphère, Nanosphere, Nanosfera, Particule sphérique, Spherical particle, Partícula esférica, Procédé sol gel, Sol gel process, Procedimiento sol gel, Protéine, Protein, Proteína, Silice, Silica, Sílice, Synthèse, Synthesis, Síntesis, Séparation, Separation, Separación, SiO2, His-tagged protein, Protein separation, Silica nanospheres, and Surface modification

Silica (SiO2) nanospheres (NSs) with immobilized metal ligands have been prepared for the affinity separation of proteins. First, SiO2 NSs were prepared by controlled hydrolysis of tetraethoxysilane in a basic aqueous-ethanol solution. Then through reaction of iminodiacetic acid (IDA) with 3-glycidoxypropyltrimethoxysilane and immobilization of them onto the surfaces of above SiO2 NSs, novel affinity adsorbents with IDA chelating groups were obtained. After chelating Ni2+ ions, the SiO2-IDA-Ni2+ NSs were applied to separate his-tagged proteins directly from the mixture of lysed cells. The SiO2-IDA-Ni2+ NSs present negligible nonspecific protein adsorption and high protein binding ability (28.3 mg/g).

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Physicochimie des réactions induites par rayonnements, particules et ultrasons, Physical chemistry of induced reactions (with radiations, particles and ultrasonics), Photochimie, Photochemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Capteur mesure, Measurement sensor, Captador medida, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Matériau poreux, Porous material, Material poroso, Mordançage, Etching, Mordentado, Nanoparticule, Nanoparticle, Nanopartícula, Nanosphère, Nanosphere, Nanosfera, Particule sphérique, Spherical particle, Partícula esférica, Photocatalyse, Photocatalysis, Fotocatálisis, Procédé sol gel, Sol gel process, Procedimiento sol gel, Structure, Estructura, Synthèse, Synthesis, Síntesis, O Zn, ZnO, Gas sensitivity, and Porous structure

Monodispersed porous ZnO nanospheres with diameters about 400―600 nm were successfully fabricated by a facile and effective cationic surfactant assisted selective etching strategy. The as-synthesized ZnO materials were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope and N2 adsorption―desorption. These samples were used as the gas sensor, showing the high, stable and fast response to acetone, revealing the potential application as gas sensor to detect acetone. In addition, the photocatalytic degradation property of the porous ZnO nanospheres for methyl orange (MO) under UV irradiation was investigated. The degradation efficiency of MO reaches 96 % of the porous ZnO samples after 50 min of UV-light irradiation.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Matériau poreux, Porous material, Material poroso, Libération, Release, Liberación, Mésoporosité, Mesoporosity, Mesoporosidad, Nanotube carbone, Carbon nanotubes, Procédé sol gel, Sol gel process, Procedimiento sol gel, Silice, Silica, Sílice, Synthèse, Synthesis, Síntesis, Vecteur médicament, Drug carrier, Vector medicamento, pH, SiO2, Controlled release, Mesoporous silica, and pH-responsive

A novel mesoporous silica tubes (MMT) which possessed pH-sensitive controlled release ability had been fabricated and synthesized by using carbon nanotubes (CNTs) as template. The sample replicated the morphologies of the CNTs successfully. The Brunauer―Emmett―Teller surface area of the materials can reach 1,017 m2 g-1 with the pore size of 3.8 nm. As a model drug, metformin HCl was applied to study the drug loading and control release ability of the materials. MMT possesses higher drug loading ratio (36 %) than that of MCM-41 (27.5 %). The release kinetics were studied in simulated gastric fluid (pH = 1.2) and in simulated proximal intestine fluid (pH = 7. 4), respectively. The result shows that the delivery systems exhibit well pH-sensitive control release ability and the as-synthesized materials have potential application in biomedical field.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Matériau poreux, Porous material, Material poroso, Composé de métal de transition, Transition element compounds, Epoxyde, Epoxide, Epóxido, Macroporosité, Macroporosity, Macroporosidad, Procédé sol gel, Sol gel process, Procedimiento sol gel, Structure, Estructura, Synthèse, Synthesis, Síntesis, Séparation phase, Phase separation, Separación fase, Zircone, Zirconia, Zircona, ZrO2, Bicontinuous, Macroporous, Monolithic, and Sol-gel process

Monolithic macroporous zirconia was synthesized through a new method involving an epoxide-driven sol-gel method accompanied by a spontaneous phase separation. The sol-gel transition utilized inorganic salt ZrCl4 as primary precursor and propylene oxide as matrix former through a ring-opening reaction. Phase separation was induced with poly-(ethylene oxide) (PEO) and its tendency was adjusted by incorporating Mg2+/Y3+ and N-methylformamide (NFA) in starting solution. The morphology of the dried gel changed from a solid nanoporous structure through a phase separated macroporous bicontinuous structure to aggregates particles when varying Mg2+ or Y3+, NFA and PEO composition. An appropriate choice of the starting composition, by which the phase separation and gelation occurred parallel, allows the fabrication of macroporous zirconia monoliths in large dimensions (Φ = 30 mm, h = 8 mm). The skeleton of the monolithic macroporous zirconia gels possess a BET surface area of 271.7 m2/g. Accordingly, the effect and mechanisms of Mg2+, Y3+ and NFA during gelation process were proposed in detail. Moreover, Mg2+ or Y3+ might also act as stabilizer to form the magnesia or yttria stabilized tetragonal or cubic zirconia after the samples were heat-treated at high temperature (800 °C).

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Théorie des réactions, cinétique générale. Catalyse. Nomenclature, documentation chimique, informatique chimique, Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry, Catalyse, Catalysis, Physicochimie des réactions induites par rayonnements, particules et ultrasons, Physical chemistry of induced reactions (with radiations, particles and ultrasonics), Photochimie, Photochemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Bismuth Oxyde, Bismuth Oxides, Bismuto Óxido, Bleu méthylène, Methylene blue, Azul metileno, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Composé ternaire, Ternary compound, Compuesto ternario, Dégradation photochimique, Photochemical degradation, Degradación fotoquímica, Electrofilage, Electrospinning, Electrohilado, Photocatalyse, Photocatalysis, Fotocatálisis, Procédé sol gel, Sol gel process, Procedimiento sol gel, Rayonnement visible, Visible radiation, Radiación visible, Synthèse, Synthesis, Síntesis, Vanadium Oxyde, Vanadium Oxides, Vanadio Óxido, BiVO4, Microribbon, and Photocatalytic activity

Quasi one-dimensional (1D) BiVO4 microribbons were prepared by sol-gel combined with electrospinning method. The prepared samples were characterized with thermogravimeter, differential scanning calorimeter, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy and UV-vis absorbance spectroscopy. The as-prepared products showed a well-defined ribbon structure with 2-3 μm in width, tens of microns in length and about 0.4 μm in thickness, respectively and exhibited excellent photocatalytic activity in the photodegradation of methylene blue under visible light irradiation.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Physicochimie de surface, Surface physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Matériau poreux, Porous material, Material poroso, Microstructure, Microestructura, Mésoporosité, Mesoporosity, Mesoporosidad, Nanoparticule, Nanoparticle, Nanopartícula, Physisorption, Fisisorción, Procédé sol gel, Sol gel process, Procedimiento sol gel, Silice, Silica, Sílice, Synthèse, Synthesis, Síntesis, SiO2, Alkanolamines, N2 physisorption, Silica nanoparticles, and Sol―gel

The effect of secondary (diethanolamine) and tertiary (triethanolamine) alkanolamines as catalysts on the formation of mesoporous Stöber silica nanoparticles by sol-gel method was studied. The particles were characterized by thermogravimetry and differential thermal analysis, Fourier transform infrared spectroscopy, N2 physisorption measurements, and field emission scanning electron microscopy. By using ammonia and different alkanolamines as catalysts, the Brunauer―Emmet―Teller (BET) surface area and pore volume increased in the order of ammonia < diethanolamine < triethanolamine. A maximum BET surface area of 140.1 m2 g―1 and pore volume of 0.66 cm3 g―1 were obtained from triethanolamine catalyzed silica particles. The average particle size of silica prepared by ammonia and different alkanolamines as catalysts decreased in the order of ammonia > diethanolamine > triethanolamine. The role of different alkanolamines on the textural properties and particle size of silica is explained in terms of their relative steric hindrance and basicity.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Photoélectrochimie. Electrochimiluminescence, Photoelectrochemistry. Electrochemiluminescence, Etat colloïdal et états dispersés, Colloidal state and disperse state, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Composé binaire, Binary compound, Compuesto binario, Composé de métal de transition, Transition element compounds, Conversion chimique, Chemical conversion, Conversión química, Nanobâtonnet, Nanorod, Nanopalito, Oxyde de zinc, Zinc oxide, Zinc óxido, Particule enrobée, Coated particle, Partícula envuelta, Photoélectrochimie, Photoelectrochemistry, Fotoelectroquímica, Procédé sol gel, Sol gel process, Procedimiento sol gel, Sulfure de cuivre, Copper sulfide, Cobre sulfuro, Synthèse, Synthesis, Síntesis, Cu2S, Dissociation de l'eau, Water splitting, O Zn, ZnO, Photoelectric performance, and SILAR

In this work, two kinds of ZnO/Cu2S core/shell nanorods (NRs) have been successfully synthesized from ZnO NRs for photoelectrochemical (PEC) water splitting by a versatile hydrothermal chemical conversion method (H-ZnO/Cu2S core/shell NRs) and successive ionic layer adsorption and reaction method (S-ZnO/Cu2S core/shell NRs), respectively. The photoelectrode is composed of a core/shell structure where the core portion is ZnO NRs and the shell portion is Cu2S nanoparticles sequentially located on the surface. The ZnO NRs array provides a fast electron transport pathway due to its high electron mobility properties. The optical property of both two kinds of core/shell NRs was characterized, and enhanced absorption spectrum was discovered. Our PEC system produced very high photocurrent density and photoconversion efficiency under 1.5 AM irradiation for hydrogen generation. On the basis of a versatile chemical conversion process based on the ion-by-ion growth mechanism, H-ZnO/Cu2S core/shell NRs exhibit a much higher photocatalytic activity than S-ZnO/Cu2S core/shell NRs. The photocurrent density and photoconversion efficiency of H-ZnO/Cu2S core/shell NRs are up to 20.12 mA cm―2 at 0.85 V versus SCE and 12.81 % at 0.40 V versus SCE, respectively.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Physicochimie des réactions induites par rayonnements, particules et ultrasons, Physical chemistry of induced reactions (with radiations, particles and ultrasonics), Photochimie, Photochemistry, Physicochimie de surface, Surface physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Composé de métal de transition, Transition element compounds, Adsorption, Adsorción, Aérogel, Aerogel, Aerógel, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Effet pression, Pressure effect, Efecto presión, Matériau poreux, Porous material, Material poroso, Microstructure, Microestructura, Modification, Modificación, Oxyde de silicium, Silicon oxides, Oxyde de titane, Titanium oxide, Titanio óxido, Photocatalyse, Photocatalysis, Fotocatálisis, Pore, Poro, Procédé sol gel, Sol gel process, Procedimiento sol gel, Silice, Silica, Sílice, Structure pores, Pore structure, Estructura poros, Synthèse, Synthesis, Síntesis, Séchage, Drying, Secado, SiO2, Adsorption/photocatalysis, Ambient pressure drying, Surface modification, and TiO2-SiO2

TiO2-SiO2 composite aerogels were prepared via ambient pressure drying by sol-gel and surface modification for both the sol and gel samples. The organosilane reagents of decamethyltetrasiloxane (DMTSO)/trimethylchlorosilane (TMCS) and hexamethyldisiloxane (HMDSO)/ TMCS were introduced into the TiO2-SiO2 composite sol for pre-modification respectively, and subsequently the TMCS/ hexane solution was used for surface modification of the obtained TiO2-SiO2 composite gel. The effects of sol pre-modification on the microstructure and pore characteristics of TiO2-SiO2 composite aerogels were investigated. The results indicate that HMDSO/TMCS coupling reagents is more appropriate for the pre-modification of TiO2-SiO2 composite sol than the DMTSO/TMCS reagents. The best volume ratio of HMDSO/TMCS/composite sol for preparing mesoporous TiO2-SiO2 composite aerogels is in the range of 1:0.33:10-1:1.0:10, with which the specific surface area and pore volume of the obtained TiO2-SiO2 composite aerogels are 492-645 m2/g and 2.63-2.85 m3/g, respectively. The results of adsorption and photocatalytic degradation of rhodamine B show that the as-prepared TiO2-SiO2 composite aerogels have higher adsorption/photocatalysis. Particularly, the as-prepared TiO2-SiO2 composite aerogels with HMDSO/TMCS showed prominent adsorption capability with the adsorption rate attaining to 89.4 % within 60 min.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Composé binaire, Binary compound, Compuesto binario, Nanostructure, Nanoestructura, Oxyde d'étain, Tin oxide, Estaño óxido, Procédé sol gel, Sol gel process, Procedimiento sol gel, Synthèse, Synthesis, Síntesis, Ultrason, Ultrasound, Ultrasonido, O Sn, SnO2, Metal oxides, Nanostructures, Sol-gel, and Ultrasonic

Fluorine doped SnO2 nanostructures were grown using ultrasonic assisted sol-gel method. The gel was obtained by dissolving stannous chloride in methanol with ammonium fluoride as dopant followed by irradiation with ultrasonic vibrations. Obtained samples were characterized by structural, morphological and optical studies. All the peaks in the X-ray diffractograms are identified and indexed as tetragonal cassiterite structure. Negative slope of William-son-Hall plots indicates compressive strain. Particle size of SnO2 nanostructures is decreases with increases in concentration of fluorine doping. Atomic force microscopy, scanning electron microscopy and transmission electron microscopy studies confirm the formation of ring like porous structures and then hollow tube like growth with increase in the fluorine concentration. Peaks in Raman spectra also indicate strong confinement in SnO2 particles. Distinct peaks in the PL spectra make the structure suitable for photovoltaic applications.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Sciences appliquees, Applied sciences, Energie, Energy, Energie naturelle, Natural energy, Energie solaire, Solar energy, Conversion photovoltaïque, Photovoltaic conversion, Cellules solaires. Cellules photoélectrochimiques, Solar cells. Photoelectrochemical cells, Composé de métal de transition, Transition element compounds, Cellule solaire à colorant, Dye-sensitized solar cell, Célula solar sensibilizada tinte, Coefficient diffusion, Diffusion coefficient, Coeficiente difusión, Hydroxyde, Hydroxides, Hidróxido, Oxyde de titane, Titanium oxide, Titanio óxido, Particule, Particle, Partícula, Procédé sol gel, Sol gel process, Procedimiento sol gel, Propriété optique, Optical properties, Propiedad óptica, Synthèse, Synthesis, Síntesis, Dye-sensitized solar cells, Electron diffusion coefficient, Electron transport time, Ethylenediamine, Modified sol―gel process, N-doped TiO2, and [Ti(NH2CH2CH2NH2)x(H2O)y]zOH

To promote the photoelectric conversion efficiency of solar cell, N-doped TiO2 particles are introduced as working electrodes in dye-sensitized solar cells. The N-doped TiO2 particles (N―en―TiO2) are easily synthesized from [Ti(NH2CH2CH2NH2MH2O)y]zOH (aquaethylenediaminetitanium(IV) hydroxide) complex using a modified sol―gel process. The produced N―en―TiO2 particles show rice-shapes of 25-50 nm and their band-gaps become to be shorter than that of TiO2. The N―en―TiO2 particles are applied to working electrode layers in dye-sensitized solar cells, and on comparing the performances of pure TiO2 and N―en2―TiO2―DSCs, the latter shows good performance with a solar energy conversion efficiency of ~5.54 % versus the former of 4.21 % respectively with a notable photocurrent enhancement. Particularly, the N-en2―TiO2―DSCs exhibit relatively low charge transfer resistance at counter electrode and electron transfer resistance from dye/TiO2/photoanode, slower recombination times, faster electron transport times, and higher electron diffusion coefficients than non-doped TiO2―DSCs.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, Etat colloïdal et états dispersés, Colloidal state and disperse state, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Alcool, Alcohol, Composé benzénique, Benzenic compound, Compuesto bencénico, Composé nitro, Nitro compound, Compuesto nitro, Phénols, Phenols, Fenoles, Argent, Silver, Plata, Composé de métal de transition, Transition element compounds, Electrocatalyse, Electrocatalysis, Electrocatálisis, Matériau composite, Composite material, Material compuesto, Microparticule, Microparticle, Micropartícula, Microsphère, Microsphere, Microsfera, Métal transition, Transition metal, Metal transición, Oxyde de nickel, Nickel oxide, Níquel óxido, Particule sphérique, Spherical particle, Partícula esférica, Procédé sol gel, Sol gel process, Procedimiento sol gel, Synthèse, Synthesis, Síntesis, Nanofeuillet, Nanosheet, Phénol(4-nitro), Ag/NiO composites, Empty microspheres, Nanosheets, and p-Nitrophenol

Ag/NiO composite nanosheets and empty microspheres were fabricated by calcining the precursors synthesized via hydrothermal and solvothermal procedures involved four methods. The as-prepared samples were characterized by thermogravimetric and differential thermal analysis, X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and field emission scanning electron microscopy, respectively. The electrocatalytic properties of Ag/NiO composites modified on a glassy carbon electrode for p-nitrophenol reduction were investigated. The results showed that Ag/NiO composites exhibited highly enhanced electrocatalytic activity than a bare glassy carbon electrode, for not only the peak current increased clearly but also the corresponding peak potential decreased markedly. As a comparison, two NiO samples were used and the results showed that the peak current has an increase but the peak potentials have a slight decrease by comparing to a bare glassy carbon electrode. The Ag/NiO composites have the potential application in the electrocatalysis for the reduction of nitrophenol materials.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Composé binaire, Binary compound, Compuesto binario, Europium, Europio, Luminescence, Luminiscencia, Nanobâtonnet, Nanorod, Nanopalito, Procédé sol gel, Sol gel process, Procedimiento sol gel, Silice, Silica, Sílice, Synthèse, Synthesis, Síntesis, SiO2, Silica nanorods, and Sol-gel method

Uniform Eu3+ -doped SiO2 nanorods were synthesized through a simple sol-gel method using cetyltrimethylammonium bromide (CTAB) as surfactant template and tetraethylorthosilicate as silicon source. X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectrum, scanning electron microscope (SEM), transmission electron microscopy, and photoluminescence spectra were employed to characterize the products in detail. The nanorods have good uniformity and their diameters and lengths are in the range of 200-300 and 500-700 nm through the SEM images, respectively. The formation of the nanorods was studied by taking SEM images after different aging time. The experimental results indicate that CTAB plays a crucial role in the formation of the silica nanorods. The luminescence of Eu3+-doped SiO2 nanorods is dominated by red-emission around 612 nm due to intra-atomic 4f → 4f (5D0 → 7F2) transition of Eu3+ ions. Furthermore, the effect of doping concentrations of Eu3+ ions on the luminescence was investigated.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Couche mince, Thin film, Capa fina, Cristallinité, Crystallinity, Cristalinidad, Procédé sol gel, Sol gel process, Procedimiento sol gel, Structure, Estructura, Synthèse, Synthesis, Síntesis, Dielectric, Patch antenna, Return loss, Sol-gel method, and Spherical structure

Zinc aluminate compounds have been dispersed in silica matrix prepared by sol-gel method with different compositions for (1 ― x)ZnAl2O4-xSiO2. Continuous stirring of ethylene glycol solution contained zinc nitrate, aluminium nitrate and silicon dioxide to produces gel precursor. Structural and morphological studies of (1 ― x)ZnAl2O4-xSiO2 thin films were examined by field emission scanning electron microscopy (FESEM) and X-ray diffractometer (XRD) analysis. The FESEM images showed the spherical structures with porosity for (1 ― x) ZnAl2O4-xSiO2 thin films. XRD analysis indicated that the crystallite size for (1―x)ZnAl2O4-xSiO2 increased from 39.79 to 44.34 nm. Fourier transform infra-red analysis showed that the existence of H2O molecules and the presence of nitrate group within the samples. Dielectric permittivity (εr) of (1 ― x)ZnAl2O4-xSiO2 samples were measured within frequency range from 1 Hz to 1 MHz. The dielectric permittivity, εr decreased as frequency was applied to the sample. The performance of the patch antenna can be measured using return loss analysis. The highest result shows that the patch antenna resonated at frequency 3.46 GHz and gives ―14.25 dB return loss bandwidth.

General chemistry, physical chemistry, Chimie générale, chimie physique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Gels colloïdaux. Sols colloïdaux, Colloidal gels. Colloidal sols, Acide carboxylique, Carboxylic acid, Acido carboxílico, Acide gras saturé, Saturated fatty acid, Acido graso saturado, Métal transition, Transition metal, Metal transición, Acide palmitique, Palmitic acid, Palmítico ácido, Caractérisation, Characterization, Caracterización, Electrochimie, Electrochemistry, Electroquímica, Lithium, Litio, Procédé sol gel, Sol gel process, Procedimiento sol gel, Spinelle, Spinel, Espinela, Spinelles, Spinels, Espinelas, Synthèse, Synthesis, Síntesis, Zinc, Sol―gel method, Spectral and electrochemical studies, Spinel cathode, and Zinc and praseodymium

LiMn2O4 and LiZnxPryMn2―x―yO4 (x = 0.10― 0.24; y = 0.01―0.10) powders have been synthesized by sol―gel method using palmitic acid as chelating agent. The synthesized samples have been subjected to thermo gravimetric and differential thermal analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDAX). The sol―gel route bestows low calcination temperature, shorter heating time, high purity, good control over stoichiometry, small particle size, high surface area, good surface morphology and better homogeneity, The XRD patterns reveal high degree of crystallinity and better phase purity. SEM and TEM images exhibit nano-sized nature particles with good agglomeration. EDAX peaks of Zn, Pr, Mn and O have been confirmed in actual compositions of LiMn2O4 and LiZnxPryMn2―x―yO4. Charge―discharge studies of pristine spinel LiMn2O4 heated at 850 °C delivers discharge capacity of 132 mA h g-1 corresponding to columbic efficiency of 73 % during the first cycle. At the end of 10th cycles, it delivers maximum discharge capacity of 112 mA h g-1 with columbic efficiency of 70 % and capacity fade of 0.15 mA h g-1 cycle-1 over the investigated 10 cycles. Inter alia, all dopants concentrations, LiZn0.10Pr0.10Mn1.80O4 exhibits the better cycling performance (1st cycle discharge capacity: 130 mA h g-1 comparing to undoped spinel 132 mA h g-1) corresponding to columbic efficiency of 73 % with capacity fade of 0.12 mA h g-1 cycle-1.