Photoluminescence
Mostrando 1-12 de 216 artigos, teses e dissertações.
-
1. Synthesis and characterization of α-SnWO4 powders obtained by microwave-assisted hydrothermal method
Abstract The structural, morphological, and optical properties of α-SnWO4 synthesized by microwave-assisted hydrothermal method at 150 °C for different times were investigated. XRD revealed the formation of the orthorhombic phase, without the presence of a secondary phase. The sample processed for 64 min showed a reduction in unit cell volume, suggesting a
Cerâmica. Publicado em: 2022
-
2. 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
-
3. Bioconjugation Between CdTe Quantum Dots and a Cationic Protein: An Analytical Method to Determine Protamine in Drug and Urine Samples
CdTe quantum dots (QD-CdTe) functionalized with mercaptosuccinic acid (MSA) were synthesized in an aqueous medium, varying synthesis time from 0.5 to 4 h. The nanoprobe were characterized by a direct relationship between synthesis time and QD size (2.61-3.04 nm). The QD-CdTe-MSA interacted with protamine (PT), a cationic protein, forming a bioconjugate, thus
J. Braz. Chem. Soc.. Publicado em: 2021-06
-
4. 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
-
5. INCORPORAÇÃO DE RODAMINA B EM MEMBRANA DE POLIAMIDA PELO MÉTODO DA ADSORÇÃO
We have incorporated rhodamine into polyamide membranes by additive manufacture selective laser sintering technology. Incorporation into 0.5 cm2 membranes was conducted at different pH values and constant temperature of 25 oC. The amounts of incorporated dye were determined by a calibration curve, and analyses showed rhodamine incorporation in the order of 1
Quím. Nova. Publicado em: 2021-02
-
6. MÉTODO MANUAL PARA DEPOSIÇÃO DE TINTAS FOTOLUMINESCENTES BASEADAS EM LOFS MISTAS APLICADO A CODIFICAÇÃO DE DOCUMENTOS
In this work, the process of synthesis of Metal-Organic Frameworks containing lanthanide ions (LOFs), accelerated via a precipitating agent, capable of accelerating the process of nucleation of MOF crystals, in order to explore the optical properties of this precursor solution (SP_Gd/EU-MOF), as a quick-response photoluminescent material in the coding of off
Quím. Nova. Publicado em: 2020-12
-
7. 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
-
8. NANOCRISTAIS DE PEROVSKITAS COLOIDAIS: HISTÓRICO, PROPRIEDADES E APLICAÇÕES
Recently, a new class of materials, the Perovskite Nanocrystals, also known as perovskite quantum dots (PQDs) has emerged. Perovskite nanocrystals are promising in optoelectronics due to their quantum confinement properties, narrow photoluminescence bands with short decay times, optically tunable bandgaps, easy surface passivation and high photoluminescent q
Quím. Nova. Publicado em: 2020-09
-
9. Transmissive to Dark Electrochromic and Fluorescent Device Based on Poly(fluorene-bisthiophene) Derivative
Films of a poly(fluorene-bisthiophene) derivative, named PFBT, were electrodeposited onto indium tin oxide (ITO) electrodes and their electrochromic and fluorescence properties were investigated. Such films displayed color variation from yellow, in the neutral state, to green, in the oxidized state, as shown by tracking of the CIE (Commission Internationale
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
-
10. The Influence of Different Ammonium Cations on the Optical Properties of Tetrakis GdIII and EuIII Complexes
A series of tetrakis-β-diketonate Q+[Ln(β-dik)4]–, where Ln = GdIII or EuIII, Q = ammonium cations and β-dik = tta (2-thenoyltrifluoracetone) or bmdm (1-(4-tert-butylphenyl)-3-(4-methoxyphenyl)-1,3-propanedione) have been synthesized and characterized. The environment surrounding the EuIII ion depends on the lateral groups of the ligand and on the alkyl
J. Braz. Chem. Soc.. Publicado em: 12/08/2019
-
11. Hydrothermal Synthesis to Water-stable Luminescent Carbon Dots from Acerola Fruit for Photoluminescent Composites Preparation and its Application as Sensors
Carbon dots (C-dots) possess the attractive properties of high stability, low toxicity, good water solubility, simple synthetic routes as well as size and excitation-dependent photoluminescence (PL).The aim of this work was to synthesize photoluminescent C-dots by hydrothermal method using acerola fruit (Malpighiaemarginata) as a row material, since this fru
Mat. Res.. Publicado em: 06/06/2019
-
12. 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