articles+ search results

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Composé de métal de transition, Transition element compounds, Matériau poreux, Porous material, Material poroso, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Mésoporosité, Mesoporosity, Mesoporosidad, Oxyde de titane, Titanium oxide, Titanio óxido, Photocatalyse, Photocatalysis, Fotocatálisis, Protection environnement, Environmental protection, Protección medio ambiente, Silice, Silica, Sílice, Synthèse, Synthesis, Síntesis, Photocatalyseur, Photocatalyst, SiO2, Hierarchical macro-mesoporous silica, Si-Cr-Ti, and Visible-light driven photocatalysis

Hierarchical macro-mesoporous silica materials co-incorporated with Crand Ti were directly synthesized by adopting close-packed array of polystyrene microsphere as hard template for macropore through a simple soaking-calcination way, where Si/Ti ratio was fixed at 200 and Si/Cr ratio was set between 200 and 10. Ti specie is highly dispersed in porous matrix and Cr specie mainly exists as tetra-coordinated CrO3 at higher Si/Cr ratio (Si/Cr ≥ 50), which transforms to a mixture of CrO3 and crystallized hexa-coordinated Cr2O3when Si/Cr ratio is below 50. This highly interconnected porous material co-incorporated with Cr and Ti presents highest visible-light driven photocatalytic activity at Si/Cr = 20 toward degradation of A07. Moreover, macro-mesoporous photocatalyst presents higher activity than those of macroporous and mesoporous ones at the same Si/Cr ratio. The improved visible light driven catalytic activity is mainly attributed to effective metal to metal charge transfer from Cr(VI) to Ti(IV) benefitted from the uniform dispersion of these two species in hierarchical porous silica matrix.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Dégradation photochimique, Photochemical degradation, Degradación fotoquímica, Microparticule, Microparticle, Micropartícula, Microsphère, Microsphere, Microsfera, Mécanisme, Mechanism, Mecanismo, Oxyde de bismuth, Bismuth oxide, Bismuto óxido, Particule sphérique, Spherical particle, Partícula esférica, Photocatalyse, Photocatalysis, Fotocatálisis, Protection environnement, Environmental protection, Protección medio ambiente, Précurseur, Precursor, Synthèse, Synthesis, Síntesis, Photodegradation mechanism, Visible-light photocatalysis, o-Phenylphenol, p-n junction, and β-Bi2O3/Bi2O2CO3 microspheres

Novel flower-like heterostructured β-Bi2O3/Bi2O2CO3 microspheres are synthesized by calcining a Bi2O2CO3 self-sacrifice precursor for the visible-light photocatalytic degradation of o-phenylphenol (OPP. is a widely used fungicide and preservative agent). The Bi2O2CO3 microspheres are firstly prepared under hydrothermal conditions, and then converted to Bi2O3 by thermal treatment. With increasing the calcining temperature from 250 to 500 °C, an in situ stepwise decomposition reaction take place during the course of calcination, described as: Bi2O2CO3 → β-Bi2O3/Bi2O2CO3 → β-Bi2O3 → β-Bi2O3/α-Bi2O3 → α-Bi2O3. The β-Bi2O3/Bi2O2CO3 microspheres synthesized at 300 °C exhibit excellent photocatalytic activity under visible-light irradiation, which can degrade 99.8% OPP in 45 min. And the degradation rate of the heterostructured photocatalyst is approximately 2, 2.6, 6, 13, 80, and 827 times higher than that of single P-Bi2O3, mixed β-Bi2O3 and Bi2O2CO3, commercial β-Bi2O3, α-Bi2O3, N-doped TiO2, and Bi2O2CO3, respectively. The superior photoreactivity of the β-Bi2O3/Bi2O2CO3 is attributed to the enhanced charge separation and transfer due to the formation of p-n junction with large heterojunction interface, favorable band gap energy (2.27 eV), relatively high specific surface areas (12.5 m2 g-1), and flower-like hierarchical micro/nano structures. In addition, the degradation intermediates including ethyl phenethyl ether, phenyl acetaldehyde, and phenylacetic acid are identified. And the results also reveal that the photogenerated holes and •O2- radicals are primarily reactive species in the photocatalytic system, which are the key factors responsible for the nearly complete mineralization of OPP.

General chemistry, physical chemistry, Chimie générale, chimie physique, 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), Sonochimie, Ultrasonic 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, Emulsions. Microémulsions. Mousses, Emulsions. Microemulsions. Foams, Graphène, Graphene, Matériau composite, Composite material, Material compuesto, Mousse (émulsion), Foam, Espuma, Nanoparticule, Nanoparticle, Nanopartícula, Sonochimie, Sonochemistry, Sonoquímica, Supercondensateur, Supercapacitor, Supercondensador, Synthèse, Synthesis, Síntesis, Ultrason, Ultrasound, Ultrasonido, 3D foam, and Composite

Graphene and its derivatives have attracted much attention in application of electrochemical devices. Construction of three-dimensional (3D) heterostructured composites is promising for establishing high-performance devices, which enables large surface area, facilitated ion and electron transport, and synergistic effects between multicomponents. Here, we report a simple and general sonochemical-assisted synthesis to prepare various 3D porous graphene/nanoparticle (i.e., Pt, Au, Pd, Ru, and MnO2) foams using colloidal template. The 3D porous network structure of composite foams significantly improves a large surface area of around 550 m2 g-1 compared to the bare graphene (215 m2 g-1). This unique structure of 3D graphene/MnO2 enables further improvement of electrochemical characteristics, compared with bare graphene/MnO2 composite, showing a high specific capacitance of 421 F g-1 at 0.1 A g-1, high rate capability (97% retention at 20 A g-1). and good cycling performance (97% retention over 1000 cycles). Moreover, electrochemical impedance analysis demonstrates that electron and ion transfer are triggered by 3D porous structure.

General chemistry, physical chemistry, Chimie générale, chimie physique, 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), Sonochimie, Ultrasonic 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, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Chimie verte, Green chemistry, Química verde, Iodure de cuivre, Copper iodide, Cobre ioduro, Nanoparticule, Nanoparticle, Nanopartícula, Protection environnement, Environmental protection, Protección medio ambiente, Réaction catalytique, Catalytic reaction, Reacción catalítica, Sonochimie, Sonochemistry, Sonoquímica, Synthèse, Synthesis, Síntesis, Ultrason, Ultrasound, Ultrasonido, Couplage de Sonogashira, Aryl ethynyl linked triarylamines, Cul nanoparticles, Sonogashira coupling, and Ultrasonic irradiation

A simple and green method was performed to the preparation of copper iodide nanoparticles by ultrasound approach. Consequently the synthesis of aryl ethynyl linked triarylamines was carried out through the Sonogashira coupling between iodo-substituted triarylamine and aryl acetylenes in the presence of CuI nanoparticles/Pd(PPh3)2Cl2 as an efficient catalytic system and triethylamine as the base under ultrasonic irradiation. Good to excellent yields of products and short reaction times are some of the important advantages of this solvent free protocol which were attained by both nano CuI and ultrasound conditions.

General chemistry, physical chemistry, Chimie générale, chimie physique, 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), Sonochimie, Ultrasonic 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, Composé binaire, Binary compound, Compuesto binario, Acide, Acids, Acido, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Colorant, Dyes, Colorante, Dégradation, Degradation, Degradación, Nanoparticule, Nanoparticle, Nanopartícula, Sonochimie, Sonochemistry, Sonoquímica, Sonolyse, Sonolysis, Sonólisis, Synthèse, Synthesis, Síntesis, Textile, Textil, Ultrason, Ultrasound, Ultrasonido, Nanocatalyseur, Nanocatalyst, O Zn, Sonocatalyse, Sonocatalysis, ZnO, Sonochemical synthesis, Textile dye, Ultrasonic degradation, and ZnO nanocatalyst

Undoped and Pr-doped ZnO nanoparticles were prepared using a simple sonochemical method, and their sonocatalytic activity was investigated toward degradation of Acid Red 17 (AR17) under ultrasonic (US) irradiation. Synthesized nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) techniques. The extent of sonocatalytic degradation was higher compared with sonolysis alone. The decolorization efficiency of sonolysis alone, sonocatalysis with undoped ZnO and 5% Pr-doped ZnO was 24%, 46% and 100% within reaction time of 70 min, respectively. Sonocatalytic degradation of AR17 increased with increasing the amount of dopant and catalyst dosage and decreasing initial dye concentration. Natural pH was favored the sonocatalytic degradation of AR17. With the addition of chloride, carbonate and sulfate as radical scavengers, the decolorization efficiency was decreased from 100% to 65%, 71% and 89% at the reaction time of 70 min, respectively, indicating that the controlling mechanism of sonochemical degradation of AR17 is the free radicals (not pyrolysis). The addition of peroxydisulfate and hydrogen peroxide as enhancer improved the degradation efficiency from 79% to 85% and 93% at the reaction time of 50 min, respectively. The result showed good reusability of the synthesized sonocatalyst.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Composé binaire, Binary compound, Compuesto binario, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Catalyseur, Catalyst, Catalizador, Composé de lanthanide, Lanthanide compound, Lantánido compuesto, Composé de métal de transition, Transition element compounds, Décomposition, Decomposition, Descomposición, Nanoparticule, Nanoparticle, Nanopartícula, Nanosphère, Nanosphere, Nanosfera, Oxyde d'azote, Nitrogen oxide, Nitrógeno óxido, Oxyde de cérium, Cerium oxide, Cerio óxido, Particule sphérique, Spherical particle, Partícula esférica, Protection environnement, Environmental protection, Protección medio ambiente, Protoxyde d'azote, Nitrogen protoxide, Nitrógeno protóxido, Réaction catalytique, Catalytic reaction, Reacción catalítica, CeO2, CuO, CeO2 nanospheres, CuO-CeO2 catalysts, N2O decomposition, Small CuO clusters, and Synergetic effect

High surface area CeO2 nanospheres as an active catalyst support were synthesized using glycothermal approach. Different loadings of copper (4, 6, 10 and 15 wt.%) were supported by wet impregnation method. Prepared materials were characterized by means of TEM, SEM-EDX, XRD, UV-Vis diffuse reflectance, N2 adsorption/desorption, DRIFT and H2-TPR techniques, and tested for the catalytic reaction of nitrous oxide decomposition. The best activity in the N2O degradation was found for the sample containing 10 wt.% of Cu that can be attributed to the highest number of small CuO clusters on the catalyst surface. Further increase of copper content strongly affects the dispersion and leads to the formation of less active segregated CuO phase, which was confirmed by XRD, UV-Vis and H2-TPR results. Accordingly to UV-Vis examination and DRIFT analysis using CO as a probe molecule, all solids contain Cu+1 ions which play a crucial role in the N2O decomposition mechanism. The synthesized catalysts were also tested in wet or NO containing atmospheres, where an inhibiting effect takes place and leads to shifting of conversion profiles to higher temperature by 65 and 10 °C, correspondingly. It was found out that the formation of a new, crystalline CuO·3H2O phase occurs in water vapour containing atmosphere, which can result in catalyst deactivation. However, this effect is fully reversible and the catalyst is able to replenish initial activity in dry atmosphere. Potentiality of CuO/CeO2 materials in catalytic N2O decomposition in industrial processes was confirmed by long-term stability tests performed in the period of 50 h in the presence of inhibiting gas components.

General chemistry, physical chemistry, Chimie générale, chimie physique, 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), Sonochimie, Ultrasonic 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, Matériaux poreux, Porous materials, Composé binaire, Binary compound, Compuesto binario, Matériau poreux, Porous material, Material poroso, Acide fluoroborique, Fluoroboric acid, Fluorobórico ácido, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Catalyseur sur support, Supported catalyst, Catalizador sobre soporte, Mésoporosité, Mesoporosity, Mesoporosidad, Nanoparticule, Nanoparticle, Nanopartícula, Silice, Silica, Sílice, Sonication, Sonicación, Sonochimie, Sonochemistry, Sonoquímica, Support catalyseur, Catalyst support, Soporte catalizador, Synthèse, Synthesis, Síntesis, Ultrason, Ultrasound, Ultrasonido, SiO2, Mesoporous silica nanoparticles, Pyrroloacridinones, Sonication mediated synthesis, and Supported HBF4 catalyst

Fluoroboric acid (HBF4) adsorbed on mesoporous silica nanoparticles of 600 nm dimension was synthesized and characterized by N2 adsorption, HRTEM, EDX, XPS. The applicability of silica-HBF4 was probed through the sonication assisted synthesis of pyrroloacridinones in ecofriendly solvent ethanol. Standard leaching experiment was performed to show that the reaction was heterogeneous with this recyclable catalyst.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Acide carboxylique, Carboxylic acid, Acido carboxílico, Composé de métal de transition, Transition element compounds, Acide formique, Formic acid, Fórmico ácido, Alliage, Alloys, Aleación, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Décomposition, Decomposition, Descomposición, Electrofilage, Electrospinning, Electrohilado, Hydrogène, Hydrogen, Hidrógeno, Nanofibre, Nanofiber, Nanofibra, Nanoparticule, Nanoparticle, Nanopartícula, Oxyde de titane, Titanium oxide, Titanio óxido, Photocatalyse, Photocatalysis, Fotocatálisis, Protection environnement, Environmental protection, Protección medio ambiente, Résonance plasmon surface, Surface plasmon resonance, AuPd alloy, and Formic acid decomposition

We present high-yield hydrogen production through selective photocatalytic decomposition of formic acid by using electrospun TiO2 nanofibers decorated with AuPd bimetallic alloy nanoparticles under simulated sunlight irradiation. By using only 5 mg of the AuPd/TiO2 nanofibers containing the 0.75% Au and 0.25% Pd, we could achieve an optimal H2 generation rate of 88.5 μmol h-1 with an apparent quantum yield at 365 nm as 15.6%. which is higher than that of the Pd/TiO2 and Au/TiO2 nanofibers by a factor of 1.6 and 4.5, respectively. The enhanced photocatalytic decomposition of formic acid for H2 generation could be attributed to the stronger electron-sink effect of AuPd alloy nanoparticles, the high selectivity of Pd for the dehydrogenation of formic acid, and the surface plasmon resonance effect of Au. More importantly, we demonstrate that the photocatalytic processes enable re-activation of the AuPd nanoparticles that were poisoned by CO during thermal decomposition of formic acid. As such, the presented AuPd/TiO2 nanofibers are promising materials for re-generation of H2 under mild conditions from liquid storage carrier of hydrogen. .

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Autoassemblage, Self assembly, Autoensamble, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Dégradation photochimique, Photochemical degradation, Degradación fotoquímica, Nanoparticule, Nanoparticle, Nanopartícula, Photocatalyse, Photocatalysis, Fotocatálisis, Protection environnement, Environmental protection, Protección medio ambiente, Sulfure, Sulfides, Sulfuro, Superréseau, Superlattice, Superred, Synthèse, Synthesis, Síntesis, Cuprous sulfide, Photocatalytic degradation, Scalable synthesis, and Self-assembly

Size- and shape-tunable Cu2S nanoparticles were successfully synthesized via a facile one-pot solvothermal process and appreciable yields at gram-scale were achieved in every single reaction. By meticulous observation with a high resolution transmission electron microscope, intensively existing atomic-level superlattice structures were identified and perceived as a result of the coexistence of both chalcocite and chalcocite-M phase in as-obtained Cu2S nanoparticles. Further, 3D ordered self-assemblies of pristine Cu2S nanoparticles were obtained by introducing the polar solvent, ethanol, into the non-polar colloidal dispersion systems during the post-treatment process, and thereby the double-superlattice (DSL) nanoparticle systems consisted of both atomic- and particle-level superlattice structures were achieved. And as promising photocatalysts, although the photocatalytic activity was influenced mutually by the size, shape, crystallinity, atomic-level superlattice structures of pristine Cu2S nanoparticles and their self-assembling behavior, the novel structured DSL nanoparticle systems finally demonstrated highly enhanced photocatalytic efficiency towards the degradation of methylene blue.

General chemistry, physical chemistry, Chimie générale, chimie physique, 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), Sonochimie, Ultrasonic chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Membranes, Acide, Acids, Acido, Détection, Detection, Detección, Mitochondrie, Mitochondria, Mitocondria, Potentiel membrane, Membrane potential, Potencial membrana, Sonochimie, Sonochemistry, Sonoquímica, Thérapie, Therapy, Terapia, Ultrason, Ultrasound, Ultrasonido, 5-Aminolevulinic acid, Macrophage, Mitochondrial membrane potential, Reactive oxygen species, and Sonodynamic therapy

Reactive oxygen species (ROS) elevation and mitochondrial membrane potential (MMP) loss have been proven recently to be involved in sonodynamic therapy (SDT)-induced macrophage apoptosis and necrosis. This study aims to develop an experimental system to monitor intracellular ROS and MMP in real-time during ultrasonic irradiation in order to achieve optimal effect in SDT. Cultured THP-1 derived macrophages were incubated with 5-aminolevulinic acid (ALA), and then sonicated at different intensities. Intracellular ROS elevation and MMP loss were detected in real-time by fluorospectrophotometer using fluorescence probe DCFH-DA and jc-1, respectively. Ultrasound at low intensities (less than 0.48 W/cm2) had no influence on ROS and MMP in macrophages, whereas at an intensity of 0.48 W/cm2, ROS elevation and MMP loss were observed during ultrasonic irradiation. These effects were strongly enhanced in the presence of ALA. Quantitative analysis showed that ROS elevation and MMP loss monotonically increased with the rise of ultrasonic intensity between 0.48 and 1.16 W/cm2. SDT at 0.48 and 0.84 W/cm2 induced mainly apoptosis in THP-1 macrophages while SDT at 1.16 W/cm2 mainly cell necrosis. This study supports the validity and potential utility of real-time ROS and MMP detection as a dosimetric tool for the determination of optimal SDT.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Métal transition, Transition metal, Metal transición, Argent, Silver, Plata, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Dégradation, Degradation, Degradación, Déshalogénation, Dehalogenation, Deshalogenación, Eau, Water, Agua, Electrode, Electrodes, Electrodo, Nanoparticule, Nanoparticle, Nanopartícula, Polluant, Pollutant, Contaminante, Protection environnement, Environmental protection, Protección medio ambiente, Réaction catalytique, Catalytic reaction, Reacción catalítica, SECM, Screen-printed electrodes, and Trichloromethane

Electrochemical abatement of volatile polychlorinated organic compounds for environmental applications represents a very attractive and feasible alternative for working at mild reaction conditions and reduced costs. We present herein the synthesis of three different sized Ag nanoparticles (NPs) and their electrocatalytic performance in the degradation of a model pollutant (trichloromethane, CHCl3) in aqueous media. Two different methodologies are used: A conventional study based on voltammetry and chronoamperometry and a novel screening approach based on the micropipette delivery/substrate collection (MD/SC) mode of the scanning electrochemical microscopy (SECM). This new approach allows to dose any reactant, in this case CHCl3, even if the latter cannot be electrogenerated. Moreover, we introduce here a novel platform for studying nanomaterials by reducing the current collector background contribution using disposable screen-printed array electrodes. The performance ranking obtained by the SECM for the three different samples of Ag NPs synthesized is validated by its comparison with the results obtained by chronoamperometry, which demonstrates the feasibility and the good sensitivity of SECM in electrocatalysts screening for the CHCl3 reduction reaction. In addition, SECM allows to analyze simultaneously a large number of catalysts in one single experiment under constant experimental conditions. We suggest the proper size range and the presence of abundant superficial defective sites, such as steps or kinks, as the main reasons for Ag NPs C1 exhibiting the best overall catalytic performance in trichloromethane electrochemical reduction.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Electrochimie, Electrochemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Matériaux poreux, Porous materials, Matériau poreux, Porous material, Material poroso, Métal transition, Transition metal, Metal transición, Carbone, Carbon, Carbono, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Electrochimie, Electrochemistry, Electroquímica, Fibre carbone, Carbon fiber, Fibra carbón, Mésoporosité, Mesoporosity, Mesoporosidad, Nanomatériau, Nanostructured materials, Palladium, Paladio, Platinoïde, Platinoid, Platinoide, Protection environnement, Environmental protection, Protección medio ambiente, Réduction chimique, Chemical reduction, Reducción química, Support catalyseur, Catalyst support, Soporte catalizador, Nanobobine, Nanocoil, CO2 electroreduction, Carbon nanocoils, Carbon nanofibers, and Ordered mesoporous carbon materials

Pd nanoparticles have been supported onto different novel carbon materials to be used in the electroreduction of CO2 to high-added value products. Carbon nanocoils (CNCs), carbon nanofibers (CNFs) and ordered mesoporous carbon materials (OMCs) have been studied as support of the catalysts. In addition, Pd catalyst supported onto Vulcan XC-72R has been synthesized in order to establish a comparison with the commercial support. In this way, the influence of the carbon material on the physicochemical and electrochemical properties of the catalysts for the CO2 eiectroreduction process can be analyzed. Supports presented different morphologies and structures. CNFs and CNCs exhibited a crystalline structure with well-aligned graphitic layers and OMCs a hexagonal ordered structure composed of not crystalline carbon. Finally, Vulcan presented an intermediate structure between amorphous and graphitic. These differences do not affect significantly the average Pd crystallite size, although a different metal dispersion was found depending on the carbon material. On the other hand, cyclic voltammetry studies showed that CO2 was effectively reduced to other species at the surface of Pd/C catalysts. Additionally, it was proved that these species were adsorbed onto Pd at -1.0V vs Ag/AgCl. Finally, a different catalytic activity towards the CO2 reduction reaction was observed for the different electrocatalysts, indicating an influence of the carbon support.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Métal transition, Transition metal, Metal transición, Ammoniac, Ammonia, Amoníaco, Borane, Borano, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Catalyseur, Catalyst, Catalizador, Hydrazine, Hidracina, Hydrogène, Hydrogen, Hidrógeno, Nanoparticule, Nanoparticle, Nanopartícula, Nickel, Niquel, Protection environnement, Environmental protection, Protección medio ambiente, Ammonia borane, Hydrazine borane, Hydrogen generation, Methanolysis, and Nickel nanoparticles

Herein we report the results of a detailed study on the in-situ generation of poly(N-vinyl-2-pyrrolidone) (PVP) stabilized nickel(0) nanoparticles and their catalytic activity in methanolysis of hydrazine borane and ammonia borane. PVP-stabilized nickel(0) nanoparticles with an average particle size of 3.0 ± 0.7 nm were in-situ generated from the reduction of nickel(II) 2-ethylhexanoate during the methanolysis of hydrazine borane in the presence of PVP at room temperature. Polymer stabilized nickel(0) nanoparticles could be isolated from the solution by centrifugation and characterized by UV-vis spectroscopy, XPS, TEM, and SAED. PVP-stabilized nickel(0) nanoparticles are highly active and long lived catalyst in hydrogen generation from the methanolysis of hydrazine borane and ammonia borane at ambient temperature. The results of kinetic study reveal that the methanolysis is first order with respect to catalyst concentration and zero order regarding to substrate concentration in both cases. PVP-stabilized nickel(0) nanoparticles provide 14,500 turnovers in hydrogen generation from the methanolysis of hydrazine borane and 5300 turnovers from the methanolysis of ammonia borane. They also provide an initial turnover frequency of 35.6 and 12,1 min-1 for the catalytic methanolysis of hydrazine borane and ammonia borane, respectively.

General chemistry, physical chemistry, Chimie générale, chimie physique, 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), Sonochimie, Ultrasonic chemistry, Etat colloïdal et états dispersés, Colloidal state and disperse state, Emulsions. Microémulsions. Mousses, Emulsions. Microemulsions. Foams, Dispositif, Device, Dispositivo, Détection, Detection, Detección, Eau, Water, Agua, Emulsification, Emulsificación, Emulsion huile eau, Oil water emulsion, Emulsión aceite agua, Huile, Oil, Aceite, Sonochimie, Sonochemistry, Sonoquímica, Technologie, Technology, Tecnología, Ultrason, Ultrasound, Ultrasonido, De-emulsification device, Emulsion layer detection device, and Oil-water emulsion

In this paper an oil-water de-emulsification process within large tanks using ultrasonic technology is presented. As the device would operate in hazardous areas, it should not consume an excessive amount of electrical power. Hence, the paper investigates the suitable oil-water concentrations (10-90% concentrations in step of 10%) which would lead to the fastest separation while consuming the minimum amount of power. Extensive experiments which were conducted using a powerful 20 kHz ultrasonic sensor were indicative with good repeatability that the emulsion layer with less water content (i.e. 10 to 40% water-cut) gets significantly faster separation. The experimental study was then validated through a set of finite element-based simulations for different ratios of oil water emulsions. This led to suggest a new feasible de-emulsifying device which consists of a one dimensional array of ultrasonic sensors which are vertically distributed to emit ultrasonic waves in horizontal direction and in a time multiplexed manner.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Alcool, Alcohol, Composé benzénique, Benzenic compound, Compuesto bencénico, Composé binaire, Binary compound, Compuesto binario, Composé nitro, Nitro compound, Compuesto nitro, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Catalyseur, Catalyst, Catalizador, Chlorophénol, Chlorophenol, Clorofenol, Composé du chlore, Chlorine compounds, Cloro compuesto, Nanoparticule, Nanoparticle, Nanopartícula, Nanosphère, Nanosphere, Nanosfera, Particule enrobée, Coated particle, Partícula envuelta, Particule sphérique, Spherical particle, Partícula esférica, Phénols, Phenols, Fenoles, Protection environnement, Environmental protection, Protección medio ambiente, Réduction chimique, Chemical reduction, Reducción química, Silice, Silica, Sílice, Nanocatalyseur, Nanocatalyst, Phénol(4-nitro), SiO2, 4-Chlorophenol, 4-Nitrophenol, Hydrodechlorination, Ni@Pd/KCC-1 nanocatalyst, and Reduction

In this study, a novel fibrous nano-silica (KCC-1) based nanocatalyst (Ni@Pd/KCC-1) was synthesized by modifying KCC-1 using Ni@Pd core-shell nanoparticles (NPs). The Ni@Pd/KCC-1 was used in the catalytic reduction of 4-nitrophenol (4-NP) and hydrodechlorination (HDC) of 4-chlorophenol (4-CP). KCC-1, prepared by hydrothermal method, exhibited a dandelion-like shape, high surface area, and easy accessibility of active sites. The Ni@Pd NPs possessed a magnetic nickel (Ni) core with palladium (Pd) shell structural composite. Thus, use of Ni led to the reduced consumption of Pd without sacrificing the overall catalytic performance, simultaneously making it reusable as it could be conveniently recovered from the reaction mixture by using an external magnetic field. Immobilization of the Ni@Pd NPs on KCC-1 nanospheres not only prevented their aggregation, but also significantly enhanced the accessibility of the catalytic active sites. The Ni@Pd/KCC-1 nanocatalyst displayed excellent catalytic activities for both the reduction of 4-NP and the HDC of 4-CP under green conditions. The above-mentioned approach based on fibrous KCC-1 and Ni@Pd NPs provided a useful platform for the fabrication of noble metal-based cost-effective nanocatalyst with easy accessibility, and acted as a promising candidate for numerous catalytic applications.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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 de surface, Surface physical chemistry, Echange d'ions, Ion-exchange, Zéolites: préparations et propriétés, Zeolites: preparations and properties, Matériaux adsorbants, Adsorbents, Etat colloïdal et états dispersés, Colloidal state and disperse state, Matériaux poreux, Porous materials, Matériau poreux, Porous material, Material poroso, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Charbon actif, Activated carbon, Carbón activado, Conversion, Conversión, Etat transition, Transition state, Estado transitorio, Microporosité, Microporosity, Microporosidad, Oxydation, Oxidation, Oxidación, Protection environnement, Environmental protection, Protección medio ambiente, Réaction catalytique, Catalytic reaction, Reacción catalítica, Structure pores, Pore structure, Estructura poros, Zéolite, Zeolite, Zeolita, Catalysis, NO oxidation, and Transition states

Anthropogenic NOx emissions from stationary sources to the atmosphere continue to be of concern because of their adverse effects on public health and the environment. An alternative method to conventional selective catalytic reduction to reduce the amount of NOx emissions is oxidation of NO to more soluble NO2 upstream of an absorption device. Zeolites and activated carbon are effective NO oxidation catalysts, but their oxidation mechanisms are not fully understood. Here, zeolites were evaluated as NO oxidation catalysts experimentally and theoretically to identify preferred pore structures for NO conversion to NO2 and to show mechanistic similarities to activated carbon fiber-catalyzed NO oxidation. For the 17 zeolites tested here, steady-state NO conversion is not related to their chemical composition (i.e., Si, Al, or P). However, similar to carbonaceous catalysts, steady-state NO conversion mainly depend on the zeolite's physical properties, including the zeolite's cage size, pore width, and pore volume. Zeolites with maximum free sphere diameter (Dmax) between 4.70 and 6.45 Å, or zeolites with maximum included sphere diameter (Di) between 5.71 and 7.37 Å, derived from experimental results, are most effective for NO oxidation to NO2 regardless of the zeolites' channel-to-cage ratio. A mechanism for NO oxidation proceeding through the [ONOONO] transition state (TS) is described here, challenging the reported mechanism that adsorbed C*-NO3 species are the precursors of NO2 formation. Void spaces with dimensions similar to or slightly larger (i.e., 7 Å width) than the size of the TS (4.46 Å × 4.67 Å × 6.94 Å, derived from TS calculations) are the most effective spaces for NO oxidation due to strengthened van der Waals interaction between the confined TS and pore walls of the zeolite. Criteria for screening effective zeolites for NO oxidation are proposed based on results for the 17 tested zeolites, and 82 of the 206 available zeolite codes are predicted to be effective with high steady-state NO conversion. Consistent physical geometries of zeolite pore sizes (Di = 4.70-6.45 Å or Dmax = 5.71-7.37 A) and activated carbon fiber pore widths (5-7 A) provide convincing evidence that such pore sizes are needed to provide efficient steady-state NO conversion. These results may be extended to other categories of microporous materials to choose the most appropriate material for catalytic NO conversion to NO2.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Etudes physiques et chimiques. Granulométrie. Phénomènes électrocinétiques, Physical and chemical studies. Granulometry. Electrokinetic phenomena, Composé binaire, Binary compound, Compuesto binario, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Modèle cinétique, Kinetic model, Modelo cinético, Modélisation, Modeling, Modelización, Nanoparticule, Nanoparticle, Nanopartícula, Photocatalyse, Photocatalysis, Fotocatálisis, Protection environnement, Environmental protection, Protección medio ambiente, Recombinaison, Recombination, Recombinación, Réseau neuronal, Neural network, Red neuronal, O Zn, Photocatalyseur, Photocatalyst, ZnO, ANN, Electron-hole, and Elementary photocatalytic reactions

The kinetic modeling of organic pollutant photocatalytic degradation on synthesized ZnO nanoparticles was carried out. The photodegradation kinetic characteristics were investigated under different operational parameters including light intensity, initial organic concentration, ZnO content and pH. Based on the elementary photocatalytic reactions, the new kinetic model was established for prediction of photocatalytic degradation efficiency by taking into account the apparent first order rate constant, light intensity, initial organic concentration and ZnO content. The results demonstrated that the kinetic model could predict adequately photodegradation efficiency when high concentration of photo-induced hole-electron was considered. To compare the accuracy of obtained kinetic model, an empirical kinetic model as function of operational parameters and a 3-layer perceptron neural network were developed. The performance of three models was compared with experimental data by error functions and analysis of variance (ANOVA) calculation. The obtained results showed that three developed models are in good agreement with experimental data. It was also found that there is no significant difference among the developed kinetic, empirical kinetic and artificial neural network models. It was concluded that the kinetic model is developed based on the appropriate understanding from determining elementary reactions occurred in photocatalytic degradation of dye.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, 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, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Appareils de production et de conversion d'énergie: énergie thermique, énergie électrique, énergie mécanique, etc, Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc, Piles à combustible, Fuel cells, Alcanol, Alkanol, Alcool, Alcohol, Métal transition, Transition metal, Metal transición, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Electrocatalyse, Electrocatalysis, Electrocatálisis, Hydroxyde de potassium, Potassium hydroxide, Potasio hidróxido, Hyperfréquence, Microwave, Hiperfrecuencia, Irradiation hyperfréquence, Microwave irradiation, Irradiación hiperfrecuencia, Méthanol, Methanol, Metanol, Nanoparticule, Nanoparticle, Nanopartícula, Nickel, Niquel, Noir carbone, Carbon black, Carbón negro, Oxydation, Oxidation, Oxidación, Pile combustible, Fuel cell, Pila combustión, Protection environnement, Environmental protection, Protección medio ambiente, Fuel cells, KOH, and Nickel-based electrocatalyst

Ni/C electrocatalysts were prepared by chemical deposition of nickel nanoparticles on Vulcan XC-72R carbon black using microwave irradiation technique. The time of microwave irradiation during the reduction step and nickel weight percentage were varied. This was found to affect the morphology of formed Ni/C powder as shown by TEM analysis. Increasing nickel weight percentage results in the formation of more aggregated deposits. The electrocatalytic activity of different Ni/C samples towards methanol oxidation reaction in KOH solution was studied by applying cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopic techniques. Ni/C electrocatalyst containing 30wt.% Ni [Ni/C-30] shows 5.2 times higher electrocatalytic activity than that with 10 wt.% Ni [Ni/C-10]. Heating Ni/C powder into microwave oven using the pulse mode of 30s on/10s off forms the most stable electrocatalyst for prolonged oxidation reaction. Electrochemical impedance measurements show that Ni/C-30 electrocatalyst has the lowest impedance value of 0.022 kΩ cm2, while the highest one is for Ni/C-10 [0.331 kΩ cm2] in (0.4 M methanol + 0.5 M KOH) solution at 500 mV. It confirms that Ni/C-30 has the highest electrocatalytic activity towards methanol oxidation reaction.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Matériaux poreux, Porous materials, Matériau poreux, Porous material, Material poroso, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Catalyseur, Catalyst, Catalizador, Combustion, Combustión, Mécanisme, Mechanism, Mecanismo, Mésoporosité, Mesoporosity, Mesoporosidad, Oxydation, Oxidation, Oxidación, Oxyde de manganèse, Manganese oxides, Manganeso óxido, Protection environnement, Environmental protection, Protección medio ambiente, Réaction catalytique, Catalytic reaction, Reacción catalítica, Synthèse, Synthesis, Síntesis, Catalytic oxidation of VOCs, Monolithic catalyst, Redox mechanism, and Solution combustion synthesis

Three mesoporous manganese oxide catalysts (Mn2O3, Mn3O4 and MnxOy) have been prepared, by means of the solution combustion synthesis, and tested for the total oxidation of volatile organic compounds (VOCs; ethylene, propylene, toluene and their mixture). The best results, in terms of the total oxidation of VOCs, were achieved with the Mn3O4 catalyst, which showed the highest amount of electrophilic oxygen on the surface (Oα-species). The most active powder catalyst was then deposited on a cordierite-type monolith through a novel direct synthesis and tested for the total oxidation of the VOCs mixture. The Mn3O4-based monolith exhibited high activity towards the total oxidation of VOCs, which is comparable to that obtained with powdered Mn3O4. The monolithic catalyst showed excellent catalytic activity for the total combustion of the mixture of VOCs (conversion to CO2 = 99.2% ± 0.5) over a time-on-stream of 10 h at 310 °C and no deactivation occurred during this time span.

General chemistry, physical chemistry, Chimie générale, chimie physique, Environment, Environnement, 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, Matériaux poreux, Porous materials, Alcanol, Alkanol, Alcool, Alcohol, Matériau poreux, Porous material, Material poroso, Catalyse hétérogène, Heterogeneous catalysis, Catálisis heterogénea, Conversion, Conversión, Mésoporosité, Mesoporosity, Mesoporosidad, Méthane, Methane, Metano, Méthanol, Methanol, Metanol, Oxydation partielle, Partial oxidation, Oxidación parcial, Oxyde de tungstène, Tungsten oxide, Wolframio óxido, Photocatalyse, Photocatalysis, Fotocatálisis, Protection environnement, Environmental protection, Protección medio ambiente, Photocatalyseur, Photocatalyst, WO3, CH4 conversion, and Mesoporous WO3

Mesoporous WO3 was synthesized by replicating technique using ordered mesoporous silica KIT-6 as the template. The obtained material exhibits high surface area (151 m2 g-1) and porous structure. The photocatalytic conversion of methane into methanol from an aqueous suspension containing mesoporous WO3 was studied, as well as the effect of the addition of electron scavengers (Fe3+, Cu2+ Ag+) and H2O2 species. In the presence of Fe3+ ions the production of methanol was about two and a half times higher than that of pure mesoporous WO3, which was principally attributed to the largely improved electron-hole separation in this system. However, the CO2 generation rates were also increased, mainly in the presence of Ag+ ions. It was also corroborated that extra hydroxyl radicals in the aqueous medium do not improve the generation of methanol but a noticeable increase in the formation of ethane was evidenced. This suggests that only a higher availability of HO• s adsorbed on the catalyst can enhance the performance of methanol generation in the photocatalytic process.