Novel Preparation Method and Luminescent Properties of Eu3+ Doped CdWO4 Nanorod

2013 ◽  
Vol 652-654 ◽  
pp. 664-668 ◽  
Author(s):  
Fang Lei ◽  
Hao Hong Chen ◽  
Ying Shi ◽  
Jian Jun Xie ◽  
He Feng
Keyword(s):  
Diffuse Reflectance Spectroscopy ◽  
Red Light ◽  
Luminescent Properties ◽  
X Ray Diffraction ◽  
Pxrd Pattern ◽  
Red Phosphor ◽  
Transmission Electron ◽  
Length Width ◽  
20 Nm ◽  
The Eu

Eu3+ doped CdWO4 nanorods, with nearly uniform nanoscale was synthesized via a novel simple hydrothermal method easy for commercial run at 160 °C, of which the average dimensions are about 250, 50 and 20 nm in length, width and height respectively from the result of transmission electron microscopy (TEM). Powder X-ray diffraction (PXRD) pattern shows the product is pure wolframite structure. Different from undoped products showed brilliant blue-green irradiation and block crystals with multi-emission bands in red light range, the Eu doped nanorods give preferred strong 5D0→7F2 transition and are excellent red phosphor with high color purity supported by the photoluminescent (PL) measurements and ultraviolet visible diffuse reflectance spectroscopy (UV-Vis DRS). This suggests that a combination of the Eu3+ doped and undoped products are potential to realize the white lighting LED with blue, green and red components.

scholarly journals Synthesis, Structure, and Luminescent Properties of Europium-Doped Hydroxyapatite Nanocrystalline Powders

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Carmen Steluta Ciobanu ◽  
Simona Liliana Iconaru ◽  
Florian Massuyeau ◽  
Liliana Violeta Constantin ◽  
Adrian Costescu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Textural Properties ◽  
Average Crystallite Size ◽  
Luminescent Properties ◽  
Nanocrystalline Powders ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Vibrational Studies ◽  
20 Nm

The luminescent europium-doped hydroxyapatite (Eu:HAp, Ca10−xEux(PO4)6(OH)2) with0≤x≤0.2nanocrystalline powders was synthesized by coprecipitation. The structural, morphological, and textural properties were well characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The vibrational studies were performed by Fourier transform infrared, Raman, and photoluminescence spectroscopies. The X-ray diffraction analysis revealed that hydroxyapatite is the unique crystalline constituent of all the samples, indicating that Eu has been successfully inserted into the HAp lattice. Eu doping inhibits HAp crystallization, leading to a decrease of the average crystallite size from around 20 nm in the undoped sample to around 7 nm in the sample with the highest Eu concentration. Furthermore, the samples show the characteristic5D0→7F0transition observed at 578 nm related to Eu3+ions distributed on Ca2+sites of the apatitic structure.

Luminescent properties of Y2O3:Eu3+ nanophosphor prepared from urea added precursor using flame spray pyrolysis

2009 ◽  
Vol 24 (8) ◽  
pp. 2584-2588 ◽  
Author(s):  
Jae Seok Lee ◽  
Se Jin Kim ◽  
Tae Kon Kim ◽  
Rajiv K. Singh ◽  
Madhav B. Ranade
Keyword(s):  
Electron Microscopy ◽  
Spray Pyrolysis ◽  
Red Light ◽  
Luminescent Properties ◽  
Flame Spray Pyrolysis ◽  
Cubic Phase ◽  
Flame Spray ◽  
X Ray Diffraction ◽  
Synthesis Conditions ◽  
Transmission Electron

Y2O3:Eu3+ nanophosphor was synthesized by flame spray pyrolysis (FSP) from urea added nitrate based liquid precursor. In this study, urea serves as fuel and subsequently provides additional heat in the flame zone during the synthesis of phosphor particles. The end product shows cubic phase Y2O3:Eu3+ nanophosphor successfully prepared by FSP without heat treatment. The influence of synthesis conditions such as different mol of urea and nitrate source materials in aqueous solution, and doping concentration on luminescent properties, were investigated. The characteristics of nanophosphor such as crystallinity and morphology under various experiments of conditions were carried out by x-ray diffraction (XRD) and field emission-scanning electron microscopy (FE-SEM). The particle size of product was found to be in the range of 20–30 nm from transmission electron microscopy (TEM). In photoluminescence (PL) properties, Y2O3:Eu3+ nanophosphor emitted red light with a peak wavelength of 609 nm when excited with 398 nm wavelength photons.

The Preparation of CaMgSi2O6: Eu3+,Li+ Red Phosphor

2011 ◽  
Vol 55-57 ◽  
pp. 413-417 ◽  
Author(s):  
Ren Qing Wang
Keyword(s):  
Red Light ◽  
Luminescent Properties ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Phosphor Particle ◽  
Solid State Method ◽  
Red Phosphor ◽  
Structure Morphology ◽  
New Type ◽  
Ultraviolet Ray

SiO2, CaO and MgO was chosen as main raw material and Solid State method was used to prepare the samples. The precursor was directly sintered at 1000°Cfor 3h to obtain new green CaMgSi2O6:Eu3+,Li+Phosphors.The effects of the content of the doping ions Eu3+ on the luminescent properties have been studied. The structure, morphology and luminescent properties of the phosphors were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM),UV and PL-PLE spectra respectively.The results showed that the CaMgSi2O6:Eu3+,Li+ was base-centered monoclinic crystals, the phosphor particle distributed uniformly.The phosphor has a strong absorptive capacity excited by 248 nm ultraviolet ray, and could emit the strong red light with the wavelength of 590nm(5D0→7F1)and 615nm(5D0→7F2). The CaMgSi2O6:Eu3+,Li+ is a new type of red fluorescent material.

Preparation, Characterization and Photoluminescence Properties of Ternary Europium Complexes Eu(DBM)3 bath Encapsulated into Aluminosilicate Zeolites

2008 ◽  
Vol 8 (8) ◽  
pp. 3959-3966 ◽  
Author(s):  
Huihui Liu ◽  
Hongwei Song ◽  
Suwen Li ◽  
Xinguang Ren ◽  
Shaozhe Lu ◽  
...  
Keyword(s):  
Luminescent Properties ◽  
Photoluminescence Properties ◽  
X Ray Diffraction ◽  
Europium Complexes ◽  
X Ray ◽  
Zeolite L ◽  
Transmission Electron ◽  
Adsorption Of Water ◽  
Field Symmetry ◽  
The Eu

To modify the photoluminescence properties the Eu(DBM)3 bath complexes were encapsulated into the sub-nanometer pores of aluminosilicates zeolites L and Yand characterized by X-ray diffraction (XRD), transmission electron micrographs (TEM), Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible (UV-vis) absorption spectra. The luminescent properties of the encapsulated composites (Eu-L and Eu-Y) were systematically studied. The results indicate that in both the two composites the crystal-field symmetry becomes lower, as a consequence, the 5D0-7F2 electronicdipole transition relative to the 5D0-7F1 magnetic-dipole transition of Eu3+ increases in contrast to the pure complexes. The outer quantum efficiency of the Eu3+ emission and the photostability of Eu3+ are both improved considerably. The adsorption of water in the composites has influence on the thermostability and decay dynamics of the Eu3+ emission. In the composite Eu-L, which contains less water the thermostability of luminescence is improved considerably and the lifetime becomes longer in comparison to the pure complexes. Overall, zeolite L is a more ideal host material for modification of lanthanide complexes.

Luminescent Properties of Gd2MoO6:Eu3+ Nanophosphor for WLEDs

2021 ◽  
Author(s):  
Yan Chen ◽  
Yuemei Lan ◽  
Dong Wang ◽  
Guoxing Zhang ◽  
Wenlong Peng ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Fluorescence Spectra ◽  
Solvothermal Method ◽  
Luminescent Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

A series of Gd2-xMoO6:xEu3+(x=0.18-0.38) nanophosphors were synthesized by the solvothermal method. The properties of this nanophosphor were characterized by x-ray diffraction (XRD), transmission electron microscope (TEM), fluorescence spectra and diffuse...

scholarly journals Hydrothermal Synthesis of Iodine-Doped Nanoplates with Enhanced Visible and Ultraviolet-Induced Photocatalytic Activities

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Jiang Zhang ◽  
Zheng-Hong Huang ◽  
Yong Xu ◽  
Feiyu Kang
Keyword(s):  
Photocatalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Oxygen Vacancies ◽  
Diffuse Reflectance Spectroscopy ◽  
Synergetic Effect ◽  
X Ray Diffraction ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Photocatalytic Activities

The iodine-doped Bi2WO6(I-BWO) photocatalyst was prepared via a hydrothermal method using potassium iodide as the source of iodine. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. The photocatalytic activity of I-BWO for the degradation of rhodamine B (RhB) was higher than that of pure BWO and I2-BWO regardless of visible light (>420 nm) or ultraviolet light (<400 nm) irradiation. The results of DRS analysis showed that the I-BWO and I2-BWO catalysts had narrower band gaps. XPS analysis proved that the multivalent iodine species including I0and were coadsorbed on the defect surface of Bi2WO6in I-BWO. The enhanced PL intensity revealed that a large number of defects of oxygen vacancies were formed by the doping of iodine. The enhanced photocatalytic activity of I-BWO for degradation of RhB was caused by the synergetic effect of a small crystalline size, a narrow band gap, and plenty of oxygen vacancies.

scholarly journals Silver Orthophosphate Immobilized on Flaky Layered Double Hydroxides as the Visible-Light-Driven Photocatalysts

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Xianlu Cui ◽  
Yaogang Li ◽  
Qinghong Zhang ◽  
Hongzhi Wang
Keyword(s):  
Visible Light ◽  
Diffuse Reflectance Spectroscopy ◽  
Diffraction Field ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Photocatalytic Activities ◽  
Visible Light Driven ◽  
Double Hydroxide ◽  
Double Hydroxides ◽  
Acid Red G

Flaky layered double hydroxide (FLDH) was prepared by the reconstruction of its oxide in alkali solution. The composites with FLDH/Ag3PO4mass ratios at 1.6 : 1 and 3 : 1 were fabricated by the coprecipitation method. The powders were characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscope, and UV-vis diffuse reflectance spectroscopy. The results indicated that the well-distributed Ag3PO4in a fine crystallite size was formed on the surface of FLDH. The photocatalytic activities of the Ag3PO4immobilized on FLDH were significantly enhanced for the degradation of acid red G under visible light irradiation compared to bare Ag3PO4. The composite with the FLDH/Ag3PO4mass ratio of 3 : 1 showed a higher photocatalytic efficiency.

CeO2/TiO2 Nanotubes Composites: Synthesis, Characterization, and Photocatalytic Properties

2012 ◽  
Vol 583 ◽  
pp. 86-90 ◽  
Author(s):  
Hai Bin Li ◽  
Xin Yong Li ◽  
Yan De Song ◽  
Shu Guang Chen ◽  
Ying Wang ◽  
...  
Keyword(s):  
Diffuse Reflectance Spectroscopy ◽  
Atomic Ratio ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
Electron Hole ◽  
Calcination Process ◽  
X Ray ◽  
Transmission Electron ◽  
Hole Recombination

TiO2nanotubes were prepared via a hydrothermal route. CeO2nanoparticles with diameters around 5nm were loaded onto the surface of TiO2nanotubes via a deposition approach followed by a calcination process. Transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-vis diffuse reflectance spectroscopy (UV-vis) were applied for the characterization of the as-prepared CeO2/TiO2nanotubes composites. The results show that CeO2particles are highly dispersed on the surface of TiO2nanotubes. The TiO2 nanotubes are modified to response to the visible light due to the combination with CeO2. The CeO2/TiO2nanotubes composites with a CeO2/TiO2atomic ratio of 2.5% show a further improvement on the photocatalytic activity for degradation of Rhodamine B in water. The presence of CeO2improves the light absorption of TiO2nanotubes and inhibits the electron-hole recombination.

scholarly journals Cypermethrin elimination using Fe-TiO2 nanoparticles supported on coconut palm spathe in a solar flat plate photoreactor

2020 ◽  
Vol 29 ◽  
pp. 2633366X2090616
Author(s):  
Ricardo Andrés Solano Pizarro ◽  
Adriana Patricia Herrera Barros
Keyword(s):  
Electron Microscopy ◽  
Flat Plate ◽  
Diffuse Reflectance Spectroscopy ◽  
Cocos Nucifera ◽  
Operating Costs ◽  
Bet Surface Area ◽  
Gas Chromatography Mass Spectrometry ◽  
X Ray Diffraction ◽  
Molar Ratios ◽  
Transmission Electron

In this research, the photocatalytic degradation of cypermethrin using iron-titanium dioxide (Fe-TiO2) nanoparticles supported in a biomaterial was evaluated. The nanoparticles of TiO2 were synthesized by the green chemistry method assisted by ultrasound and doped by chemical impregnation using Fe+3:Ti molar ratios of 0, 0.05, 0.075 and 0.1 to make efficient use of direct sunlight ( λ > 310 nm). All nanoparticles were immobilized on the surface of coconut spathe ( Cocos nucifera). The degradation was carried out at room temperature and natural pH in a flat plate solar reactor, on which the composite material was subjected. The concentration of cypermethrin was determined after 12,000 J m−2 of accumulated radiation from gas chromatography–mass spectrometry and the resulting material was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy, and Brunauer-Emmett-Teller (BET) surface area. The best results were achieved with the use of Evonik TiO2 P-25, Fe:Ti = 0 and Fe:Ti = 0.05 in suspension, with percentages of degradation of cypermethrin of 99.84%, 99.62%, and 100%, respectively. However, the materials supported on the biomaterial of coconut allowed to reach degradation percentages higher than 80%, with the advantage that it minimizes operating costs, as they are not necessarily filtering or centrifuging processes to separate the catalyst.

scholarly journals Enhanced Photocatalytic Activity of Vanadium-Doped SnO2 Nanoparticles in Rhodamine B Degradation

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
H. Letifi ◽  
Y. Litaiem ◽  
D. Dridi ◽  
S. Ammar ◽  
R. Chtourou
Keyword(s):  
Photocatalytic Activity ◽  
Rhodamine B ◽  
Crystal Size ◽  
Sno2 Nanoparticles ◽  
X Ray Diffraction ◽  
Optical Studies ◽  
Vanadium Concentration ◽  
X Ray ◽  
Transmission Electron ◽  
20 Nm

In this paper, we have reported a novel photocatalytic study of vanadium-doped SnO2 nanoparticles (SnO2: V NPs) in rhodamine B degradation. These NPs have been prepared with vanadium concentrations varying from 0% to 4% via the coprecipitation method. Structural, morphological, and optical properties of the prepared nanoparticles have been investigated by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscope (TEM), and UV-Vis and photoluminescence (PL) spectroscopy. Structural properties showed that both undoped and SnO2: V NPs exhibited the tetragonal structure, and the average crystal size has been decreased from 20 nm to 10 nm with the increasing doping level of vanadium. Optical studies showed that the absorption edge of SnO2: V NPs showed a redshift with the increasing vanadium concentration. This redshift leads to the decrease in the optical band gap from 3.25 eV to 2.55 eV. A quenching in luminescence intensity has been observed in SnO2: V NPs, as compared to the undoped sample. Rhodamine B dye (RhB) has been used to study the photocatalytic degradation of all synthesized NPs. As compared to undoped SnO2 NPs, the photocatalytic activity of SnO2: V NPs has been improved. RhB dye was considerably degraded by 95% within 150 min over on the SnO2: V NPs.

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