scholarly journals Optical Properties of Blue Phosphor

2009 ◽  
Vol 2009 ◽  
pp. 1-8 ◽  
Author(s):  
Mourad Derbal ◽  
Lakhdar Guerbous ◽  
Ouadjaout Djamel ◽  
Chaminade Jean Pierre ◽  
Mohyddine Kadi-Hanifi
Keyword(s):  
Blue Emission ◽  
Emission Spectra ◽  
Solid State Reaction Method ◽  
Photoluminescence Excitation ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Blue Phosphor ◽  
Emission Transition ◽  
Scanning Electron

(, 0.5, 1, 5, and 10 at.%) polycrystalline powders blue phosphors were prepared via the classical solid-state reaction method. X-ray diffraction (XRD), scanning electron microscope (SEM), photoluminescence excitation, and emission spectra were used to characterize phosphors. By analyzing the excitation and emission spectra of samples, the result indicates that there exists the energy transfer only from the group to the energy level of ion. On the other hand, the influence of the thulium concentration on the blue emission transition and and the emission of group are investigated.

scholarly journals Investigations of M3Al8O15:Eu3+,Dy3+ (M = Ba, Ca, Mg) phosphors

2016 ◽  
Vol 34 (2) ◽  
pp. 412-417
Author(s):  
Esra Öztürk
Keyword(s):  
Electron Microscopy ◽  
Solid State Reaction Method ◽  
Morphological Characterization ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Three Samples ◽  
Scanning Electron ◽  
The Eu

AbstractIn this work, aluminate type phosphorescence materials were synthesized via the solid state reaction method and the photoluminescence (PL) properties, including excitation and emission bands, were investigated considering the effect of trace amounts of activator (Eu3+) and co-activator (Dy3+). The estimated thermal behavior of the samples at certain temperatures (> 1000 °C) during heat treatment was characterized by differential thermal analysis (DTA) and thermogravimetry (TG). The possible phase formation was characterized by X-ray diffraction (XRD). The morphological characterization of the samples was performed by scanning electron microscopy (SEM). The PL analysis of three samples showed maximum emission bands at around 610 nm, and additionally near 589 nm, 648 nm and 695 nm. The bands were attributed to typical transitions of the Eu3+ ions.

scholarly journals Pengaruh Suhu Sintering Terhadap Sintesis Silicon Carbide (SiC) Berbahan Dasar Abu Sekam Padi dan Grafit Pensil 2B

2015 ◽  
Vol 5 (01) ◽  
pp. 31
Author(s):  
Resky Irfanita ◽  
Asnaeni Ansar ◽  
Ayu Hardianti Pratiwi ◽  
Jasruddin J ◽  
Subaer S
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Silicon Carbide ◽  
Rice Husk Ash ◽  
Sintering Temperature ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Scanning Electron

The objective of this study is to investigate the effect of sintering temperature on the synthesis of SiC produced from rice husk ash (RHA) and 2B graphite pencils. The SiC was synthesized by using solid state reaction method sintered at temperatures of 750°C, 1000°C and 1200°C for 26 hours, 11.5 hours and 11.5 hours, respectively. The quantity and crystallinity level of SiC phase were measured by means of Rigaku MiniFlexII X-Ray Diffraction (XRD). The microstructure of SiC was examined by using Tescan Vega3SB Scanning Electron Microscopy (SEM). The XRD results showed that the concentration (wt%) of SiC phase increases with the increasing of sintering temperature. SEM results showed that the crystallinity level of SiC crystal is improving as the sintering temperature increases

Photoluminescence of Eu3+-Doped La2Mo2O9 Phosphors

2010 ◽  
Vol 663-665 ◽  
pp. 332-335
Author(s):  
En Guo Wang
Keyword(s):  
Sintering Temperature ◽  
Emission Spectra ◽  
Luminescent Properties ◽  
X Ray Diffraction ◽  
Doping Amount ◽  
Obvious Effect ◽  
Reaction Method ◽  
X Ray ◽  
Europium Ion ◽  
Scanning Electron

Eu3+-doped La2Mo2O9 phosphor was fabricated by sold-state reaction method. The as-prepared samples were characterized by the application of X-ray diffraction (XRD), scanning electron microscopy (SEM), and emission spectra. The effect of the sintering temperature and doping amount of europium ion on the luminescent properties of La2Mo2O9:Eu3+ was investigated. The results show that the luminescent intensity will reach the strongest when the sintering temperature is equal to 1073 K. The Eu3+ doping amounts also have obvious effect on the luminescent properties.

Influence of Eu2+ Doped Contents on the Spectroscopic Features of Sr2-X MgSi2O7:xEu2+

2012 ◽  
Vol 476-478 ◽  
pp. 1232-1236
Author(s):  
Jia Zhe Guo ◽  
Ya Dong Li ◽  
Yan Lin Huang
Keyword(s):  
Emission Spectra ◽  
Optical Excitation ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Broad Absorption ◽  
Broad Absorption Band ◽  
Phase Purity ◽  
Reaction Method ◽  
X Ray ◽  
Uv Led

Silicate-based Sr2-xMgSi2O7:xEu2+(x=0.01, 0.03, 0.05, 0.07) phosphors were synthesized by the high temperature solid-state reaction method. Phase purity and crystal structure of the phosphors were characterized using X-ray diffraction spectrometer. The optical excitation and emission spectra of Eu2+ ion were measured using luminescence spectrometer and fluorescence spectrophotometer. The emission spectra showed a strong blue luminescence peaked around 470 nm, corresponds to the 4f65d1 →4f7 transition on Eu2+. Two different average decay time confirmed that the Eu2+ cations may occupy in two different lattice sites and presents different spectroscopic features. With a broad absorption band extending from 224 to 450 nm, it is suggestive that the phosphors have a potential application in UV-LED chips (360-400 nm).

scholarly journals Thermoelectric properties of LaFeO3 system with doped Ti, Co, Cu

2017 ◽  
Vol 126 (1B) ◽  
pp. 147
Author(s):  
Nguyen Thi Thuy
Keyword(s):  
Electron Microscope ◽  
Solid State ◽  
Room Temperature ◽  
Unit Cell Volume ◽  
Single Phase ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Scanning Electron

<p><strong>Abstract: </strong>LaFeO<sub>3</sub> system with doped Ti, Co, Cu was manufactured by solid state reaction method, it was sintered at 1250<sup>0</sup>C and 1290<sup>0</sup>C in 10 hours with a heating rate of 3<sup>0</sup>C/min. Using X-ray diffraction and Scanning Electron Microscope (SEM) to examine the structure, it reveals that samples are single-phase and orthogonal-perovskite structure describing by the Pnma space group, the unit cell volume of the samples increases when Ti, Co, Cu are doped to replace ion Fe<sup>+3</sup>. The size of particle increase while raising the temperature of sintering. Measuring the resistance which depends on temperature between the room temperature and 1000K, it can be seen that when doping Co, Cu with the nominal component La(Fe<sub>0,2</sub>Co<sub>0,2</sub>Ti<sub>0,6</sub>)O<sub>3</sub> and La(Fe<sub>0,4</sub>Cu<sub>0,1</sub>Ti<sub>0,5</sub>)O<sub>3 </sub>, the conductivity of samples increases respectively. Especially, the conductivity of Cu doped sample is higher than two other samples, and reach the highest conductivity at about 900<sup>0</sup>C, Seebeck coefficient S of La(Fe<sub>0.6</sub>Ti<sub>0.4</sub>)O<sub>3</sub> can be change from positive to negative at the temperature of around 700<sup>0</sup>C.</p>

scholarly journals Synthesis Growth and Characterization of Mn doped La1.8Sr0.20CuO4

2011 ◽  
Vol 8 (1) ◽  
pp. 97-100
Author(s):  
Manish Verma ◽  
N. P. Lalla ◽  
D. M. Phase ◽  
V. K. Ahire
Keyword(s):  
Electron Microscopy ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Phase Purity ◽  
Reaction Method ◽  
X Ray ◽  
Temperature Method ◽  
Mn Doped ◽  
Scanning Electron

Polycrystalline samples of La1.8Sr0.20Cu1-yMnyO4 (0≤y≤0.15) were synthesized by solid state reaction method. The phase purity was confirmed by powder X-ray diffraction. The scanning electron microscopy was done on the La1.8Sr0.20Cu1-yMnyO4 (0≤y≤0.15) samples. The superconductivity and Transition temperature were studied by four probe resistivity temperature method. The transition temperatures were measured nearly 37 k and were unchanged on Mn doping at Cu site in La1.8Sr0.20CuO4.

Preparation and Dielectric Behaviour of Magnetoelectric HoMnO3-BaTiO3 Composites

2007 ◽  
Vol 334-335 ◽  
pp. 1021-1024
Author(s):  
Y.J. Wu ◽  
H. Zhang ◽  
J.G. Wan ◽  
S.F. Zhao ◽  
J.M. Liu ◽  
...  
Keyword(s):  
Magnetic Ordering ◽  
Solid State Reaction Method ◽  
Phase Transformation Temperature ◽  
Antiferromagnetic Phase ◽  
X Ray Diffraction ◽  
Coupling Interaction ◽  
Impedance Analyzer ◽  
Reaction Method ◽  
X Ray ◽  
Scanning Electron

In this work, we report the magnetoelectric HoMnO3-BaTiO3 composites prepared by the solid-state reaction method. X-ray diffraction and scanning electron microscopy were used to characterize the phase composition and structures of the composites. The material/impedance analyzer was used to investigate the dielectric properties of the composites. It is shown that the composite consists of both ferroelectric ordering and magnetic ordering. The addition of BaTiO3 decreases the antiferromagnetic phase transformation temperature of the HoMnO3, indicating that there exists the coupling interaction between BaTiO3 and HoMnO3 phases.

Photoluminescence properties of Li2+xNb3xTi1−4xO3:Eu3+

2019 ◽  
Vol 12 (04) ◽  
pp. 1950057 ◽  
Author(s):  
Chao-Chao Guo ◽  
Qun Zeng ◽  
Chun-Feng Yao ◽  
Yan-Zhao Feng ◽  
Xi Chen ◽  
...  
Keyword(s):  
Solid State ◽  
Emission Spectra ◽  
Solid State Reaction Method ◽  
Photoluminescence Properties ◽  
X Ray Diffraction ◽  
Red Emission ◽  
Reaction Method ◽  
X Ray ◽  
Red Phosphors ◽  
Chromaticity Coordinate

Red phosphors with compositions of Li[Formula: see text]Nb[Formula: see text]Ti[Formula: see text]O3:3[Formula: see text]wt.% Eu[Formula: see text] [Formula: see text] were synthesized by solid-state reaction method. The samples were investigated by using X-ray diffraction (XRD) and photoluminescence spectroscopy, respectively. XRD results showed that all samples were main phase of Li2TiO3. Emission spectra of Li[Formula: see text]Nb[Formula: see text]Ti[Formula: see text]O3:3[Formula: see text]wt.% Eu[Formula: see text] powders showed strong red emission at 612[Formula: see text]nm (5D0–7F[Formula: see text] with 396[Formula: see text]nm excitation. In addition, the excitation and emission intensity increased up to [Formula: see text], and then decreased with further increasing of the x values. And the chromaticity coordinate (CIE) of the component with [Formula: see text] was superior to other components.

Effect of Sintering Temperature on (Bi2O3Fe2O3)0.8(Nb2O5)0.2

2017 ◽  
Vol 883 ◽  
pp. 3-6
Author(s):  
Sadia Tasnim Mowri ◽  
Quazi Delowar Hossain ◽  
M.A. Gafur ◽  
Aninda Nafis Ahmed ◽  
Muhammad Shahriar Bashar
Keyword(s):  
Electron Microscopy ◽  
Dielectric Property ◽  
Niobium Oxide ◽  
Sintering Temperature ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
Reaction Method ◽  
X Ray ◽  
Scanning Electron

(Bi2O3Fe2O3)0.8(Nb2O5)0.2 was synthesized by solid state reaction method. (Bi2O3Fe2O3)0.8(Nb2O5)0.2 was made for the investigation of X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Dielectric property. XRD pattern reveals that three phases were obtained with Bismuth Iron Niobium Oxide. SEM elicits that grain size increases with the enhancement of sintering temperature. Dielectric property decreases with the augmentation of frequency.

Preparation of Ag-Modified CaBiO2Cl and its Photocatalytic Ability under Visible Light

2014 ◽  
Vol 955-959 ◽  
pp. 120-126
Author(s):  
Ying Feng ◽  
Wei Huang ◽  
Chao Hao Hu ◽  
Wen Zhao ◽  
Pan Fei Jiao ◽  
...  
Keyword(s):  
Visible Light ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Photocatalytic Ability ◽  
Reaction Method ◽  
X Ray ◽  
Photocatalytic Activities ◽  
One Step ◽  
The One ◽  
Scanning Electron

Ag-modified CaBiO2Cl photocatalysts were synthesized by the one-step solid state reaction method. The microstructure and morphology of catalysts were characterized by using X-ray diffraction, Scanning electron microscopy, and Energy dispersive X-ray detector (EDS) techniques. The photocatalytic activities of pure CaBiO2Cl and Ag-CaBiO2Cl catalysts were further evaluated by degrading methylene blue (MB) under visible-light irradiation. The measured UV-vis absorption spectra indicated that the degradation of Ag-modified CaBiO2Cl has been improved by about 12% in comparison with pure CaBiO2Cl. The enhanced photocatalytic activity in Ag-modified CaBiO2Cl can be ascribed to the better morphologies of the composites due to the Ag additive.

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