Infrared Photoluminescence
Mostrando 1-12 de 31 artigos, teses e dissertações.
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1. Enhancement of Visible Light-Responsive Photocatalytic Efficiency by Using a Laccaic Acid-Modified Titanium Dioxide Photocatalyst
In this study, a laccaic acid-modified TiO2 photocatalyst (Lac-TiO2) was prepared via an impregnation method with 0.50, 1.00, 2.50, and 5.00 wt.% laccaic acid. The products’ physical properties were examined through X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), X-ray photoemission spectroscopy (XPS), UV-Vis diffused
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Improving Photoluminescence Quantum Yield of CdTe Quantum Dots Using a Binary Solvent (Water + Glycerin) in the One-Pot Approach Synthesis
The present work describes the comparison of the optical and structural properties between CdTe quantum dots (QD) synthesized in water and in the binary solvent (water + glycerin) via one-pot approach synthesis. The optical properties of the nanocrystals obtained with different synthesis parameters were characterized by UV-visible and photoluminescence spect
J. Braz. Chem. Soc.. Publicado em: 2021-04
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3. Preparation of Fluorescent Carbon-Based Dots from Waste Tire Pyrolysis
The pyrolysis of waste tire has been proposed as an alternative route to its recycling producing residual oils that can be used as fuels. In this work, a physicochemical process to obtain carbon-based dots (CBD) from carbon black (CBL) derivatives of tires is described. For this, the CBL was treated with different acids to produce CBL1 and CBL2 particles sus
J. Braz. Chem. Soc.. Publicado em: 2020-11
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4. F-127-Assisted Sol-Gel Synthesis of Gd2O3:Eu3+ Powders and Films
In the current work, the influence of Pluronic F-127 (S = F-127) and temperature on the luminescent properties of Gd2O3:Eu3+ (Gd:S = 1:2) powders and films was studied. In order to synthesize the powders and films (by the dip-coating technique), Gd2O3: Eu3+ (5 mol%) ceramics were elaborated by the sol-gel route, using gadolinium and europium nitrates as prec
Mat. Res.. Publicado em: 08/04/2019
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5. Annealing Effects on the Structural and Optical Properties of ZnO Nanostructures
ZnO nanostructures were synthesized by a proteic sol-gel method, using zinc nitrate hexahydrate and gelatin as precursors. Size and shape evolution of ZnO nanostructures were achieved by annealing temperature in the range 250-1000 ºC. The crystalline structure, morphology and optical properties of the ZnO nanoparticles were characterized by X-Ray Diffractio
Mat. Res.. Publicado em: 05/03/2018
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6. NIR Luminescence from Sol-Gel Er3+ Doped SiO2:GeO2 Transparent Gels, Nanostructured Powders and Thin Films for Photonic Applications
Samples of (1 – x)SiO2:xGeO2 compositions, containing x = 10 and 20, and doped with Er3+, were prepared by a simple sol-gel route. Homogeneous and transparent gels were synthesized and xerogels were obtained by gel annealing from 700 ºC to 1100 ºC. Films exhibiting high transmittance in the visible and near infrared were deposited by spin-coating techniq
J. Braz. Chem. Soc.. Publicado em: 2015-12
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7. Low Temperature Synthesis of Luminescent RE2O3:Eu3+ Nanomaterials Using Trimellitic Acid Precursors
[RE(TLA)·(H2O)n:Eu3+] (RE3+: Y, Gd and Lu; TLA: trimellitic acid) precursor complexes were synthesized by an one step aqueous co-precipitation method. After annealing for 1 h, RE2O3:Eu3+ nanophosphors were formed through the benzenetricarboxylate low temperature thermolysis method (500-1000 ºC). The compounds were characterized by using different technique
J. Braz. Chem. Soc.. Publicado em: 2015-12
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8. Facile Microwave-Assisted Synthesis of Lanthanide Doped CaTiO3 Nanocrystals
This article discusses a simple approach for the microwave-assisted synthesis of good quality nanosized calcium titanate crystals doped with trivalent Tm and Yb lanthanide ions. The prepared nanoparticles had a microcube-like structure and a crystallite size of ca. 47 nm. The structure of the nanocrystals was analyzed by X-ray diffraction (XRD) and scanning
J. Braz. Chem. Soc.. Publicado em: 2015-11
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9. Radiation Induced Synthesis of In2O3Nanoparticles - Part II: Synthesis of In2O3 Nanoparticles by Thermal Decomposition of Un-irradiated and γ-irradiated Indium Acetylacetonate
AbstractPure cubic phase, In2O3 nanoparticles with porous structure were synthesized by solid state thermal oxidation of un-irradiated and γ-irradiated indium acetyl acetonate in presence and absence of sodium dodecyl sulphate as surfactant. The as- synthesized In2O3nanoparticles were characterized by X-ray diffraction (XRD), fourier transformation infrared
Mat. Res.. Publicado em: 2015-10
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10. UTILIZAÇÃO DO COMPÓSITO NANOESTRUTURADO SIO2/TIO2NA FOTODEGRADAÇÃO DE CORANTES TÊXTEIS COM LUZ SOLAR NATURAL
SiO2/TiO2 nanostructured composites with three different ratios of Si:Ti were prepared using the sol-gel method. These materials were characterized using energy dispersive X-ray fluorescence, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, photoluminescence, Raman wit
Quím. Nova. Publicado em: 2015-09
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11. Novel and Fast Microwave-Assisted Synthesis of Carbon Quantum Dots from Raw Cashew Gum
Carbon quantum dots (C-dots) with average size of 9 nm were synthesized from an aqueous solution of raw cashew gum (RCG) using a novel and fast microwave-assisted technique which involves two steps. In the first step (partial depolymerization in solution) some monomer units are formed through the autohydrolysis of CG and a small amount of 5-hydroxymethyl fur
J. Braz. Chem. Soc.. Publicado em: 2015-06
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12. Electrospinning Preparation and Photoluminescence Properties of Y3Al5O12:Eu3+ Nanobelts
Novel structures of Y3Al5O12: Eu3+ (denoted as YAG: Eu3+ for short) nanobelts were fabricated by calcination of the electrospun PVP/[Y(NO3)3+Eu(NO3)3+Al(NO3)3] composite nanobelts. X-ray powder diffraction (XRD) analysis showed that YAG: Eu3+ nanobelts were cubic in structure with space group Ia3d. Fourier transform infrared spectroscopy (FTIR) analysis mani
Mat. Res.. Publicado em: 2015-04