Photocatalysis
Mostrando 1-12 de 120 artigos, teses e dissertações.
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1. Zinc tungstate: a review on its application as heterogeneous photocatalyst
Abstract ZnWO4 crystallizes in a monoclinic wolframite-like structure, which has been studied for applications in heterogeneous photocatalysis for degradation, oxidation, and reduction of various contaminants. This type of tungstate has proved to be an efficient photocatalyst under both ultraviolet and visible light irradiation and, when ZnWO4 forms a hetero
Cerâmica. Publicado em: 2022
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2. Thermal, structural and optical properties of magnetic BiFeO3 micron-particles synthesized by coprecipitation method: heterogeneous photocatalysis study under white LED irradiation
Abstract Bismuth ferrite, BiFeO3 (BFO) prepared via a coprecipitation method, was used as an effective photocatalyst for the degradation of methylene blue (MB) using a white light-emitting diode (LED-50 W) lamp. The as-prepared material was characterized by TGA, XRD, SEM-EDX, FTIR, and UV-vis-DRS techniques. The effects of experimental key parameters such as
Cerâmica. Publicado em: 2022
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3. A Comparison of the Photolytic and Photocatalytic Degradation of Triclosan: Identification of Transformation Products and Ecotoxicity Evaluation
Triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) is commonly used as an antibacterial agent in various industrial products and is often detected in wastewater effluent. Comparison was made for triclosan degradation by photolysis and TiO2 photocatalysis (under UV irradiation (125 W)) based on analysis of transformation products, together with ecotoxicity ev
J. Braz. Chem. Soc.. Publicado em: 2021-08
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4. RECENTES APLICAÇÕES DO ORGANOFOTOCATALISADOR 1,2,3,5-TETRAQUIS(CARBAZOL-9-IL)-4,6-DICIANOBENZENO EM TRANSFORMAÇÕES QUÍMICAS
Ruthenium and iridium polypyridine complexes are among the most employed photocatalysts described in literature. The broad applicability is due to the redox potentials and long half-life times of the excited state which these molecules presented. The pursuit for metal-free alternatives has been intensified in the last few years, therefore, many organic fluor
Quím. Nova. Publicado em: 2021-03
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5. Shortcomings in the training program of medical residency during the COVID-19 pandemic in Brazil. How will they be repaired?
Ruthenium and iridium polypyridine complexes are among the most employed photocatalysts described in literature. The broad applicability is due to the redox potentials and long half-life times of the excited state which these molecules presented. The pursuit for metal-free alternatives has been intensified in the last few years, therefore, many organic fluor
Rev. Bras. Ginecol. Obstet.. Publicado em: 2021-03
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6. NANOMATERIAIS PLASMÔNICOS: PARTE II. QUÍMICA DE COORDENAÇÃO DE SUPERFÍCIE E SUA APLICAÇÃO EM SENSORES E CATALISADORES
In this second part we will discuss how surface chemistry properties of plasmonic nanomaterials can be tailored by applying coordination chemistry, supramolecular and materials chemistry approaches, in which nanoparticles with well-controlled features conjugated with properly chosen molecules are the basis of functional organized structures that can be appli
Quím. Nova. Publicado em: 2020-12
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7. NANOMATERIAIS PLASMÔNICOS: PARTE I. FUNDAMENTOS DA ESPECTROSCOPIA DE NANOPARTÍCULAS E SUA RELAÇÃO COM O EFEITO SERS
We perform an analysis of plasmonic nanomaterials in a two part review, the first of which constitutes the present work. Here, attention is given to the fundamentals of metal nanoparticle optical properties. It is discussed the principles regarding the excitation of localized surface plasmon modes in nanostructures of different sizes, shapes and surrounding
Quím. Nova. Publicado em: 2020-12
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8. Sunlight-Driven Dehydrogenative Oxidation Photocatalysis by a Mononuclear Complex Acting as both Chromophore and Catalyst
Under simulated solar irradiation in the visible spectral region, the catalytically active RuIV-oxo species [Ru(O)(bpy)(tppz)]2+ (tppz = tetrapyridylpyrazine, a strongly π-accepting tridentate N, N, N-ligand) is produced directly from a single metal-to-ligand charge-transfer (MLCT) photoexcitation of the resting RuII-aquo complex [Ru(H2O)(bpy)(tppz)]2+ in a
J. Braz. Chem. Soc.. Publicado em: 2020-11
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9. Effect of Growth Parameters on the Photocatalytic Performance of TiO2 Films Prepared by MOCVD
The present study evaluated the main factors that influence the photocatalytic activity of titanium dioxide (TiO2) films grown by metalorganic chemical vapor deposition (MOCVD) at 400 and 500 °C, in different growth times. The photocatalytic behavior was analyzed by measuring the methyl orange dye degradation at different pH values. Structural and morpholog
J. Braz. Chem. Soc.. Publicado em: 2020-06
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10. Matrix Effects on the Degradation of Gemfibrozil, Hydrochlorothiazide, and Naproxen by Heterogeneous Photocatalysis
The degradation of a pharmaceutical mixture (gemfibrozil, hydrochlorothiazide and naproxen) by TiO2/UV-A in different aqueous matrices was evaluated. The matrix components affected the operational conditions, rate constants, and removal efficiency of the pharmaceuticals, as well as toxicity. For sewage treatment plant effluent, a TiO2 concentration three-fol
J. Braz. Chem. Soc.. Publicado em: 2020-06
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11. Synthesis, Characterization and Photocatalytic Activity of Au/SiO2@TiO2 Core-Shell Microspheres
By using HAuCl4 as the gold precursor, spherical Au@SiO2/TiO2 core-shell nanostructures were prepared with the sol-gel method and ethanol reflux. The preparation process was convenient and fast. The obtained samples were characterized by UV-Vis, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TE
J. Braz. Chem. Soc.. Publicado em: 2020-03
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12. Photocatalytic degradation of ferricyanide as synthetic gold mining wastewater using TiO2 assisted by H2O2
Abstract Ferricyanide Fe(CN) 6 3- is one of the most stable cyanometallic complexes present in the gold mining effluents. This cyanocomplex is hard to degrade by natural attenuation and generates a negative impact on aquatic environments. Although free cyanide (CN-) can be obtained by acidifying the solution, the CN- is lethal for all forms of life. The oxid
REM, Int. Eng. J.. Publicado em: 2020-03