scholarly journals Annealing effects on luminescent properties of Eu3+ doped Gd2Zr2O7 nanopowders

2015 ◽  
Vol 47 (3) ◽  
pp. 269-272 ◽  
Author(s):  
M.S. Rabasovic ◽  
D. Sevic ◽  
J. Krizan ◽  
M.D. Rabasovic ◽  
N. Romcevic
Keyword(s):  
Low Cost ◽  
Emission Spectra ◽  
Luminescent Properties ◽  
Combustion Method ◽  
Luminescence Properties ◽  
Camera System ◽  
Strong Emission ◽  
Structure Morphology ◽  
Annealing Effects ◽  
Size And Morphology

In this report presented are structure, morphology and luminescence properties of nanopowders based on gadolinium zirconium oxide (Gd2Zr2O7) doped by europium ions (Eu3+). The nanopowders were prepared using a flame combustion method, the most frequently used process due to the simplicity and low cost of the synthesis procedures and also due to the possibility of tailoring the size and morphology of particles. The produced material is suitable for various optical devices. The luminescence properties of synthesized nanopowders were characterized by emission spectra and luminescence lifetimes obtained by using the streak camera system. Moreover, emission spectra were obtained and compared for powders as-obtained and after additional annealing at 1200o C. Luminescence emission spectra clearly show peaks characteristic for the strong emission lines at 611 nm and 630 nm corresponding to the 5D0 ? 7F2 long lived transition.

scholarly journals Effect of nanocrystals concentration on optical and luminescent properties of PVK:ZnSe nanocomposites

2018 ◽  
Vol 36 (3) ◽  
pp. 494-500 ◽  
Author(s):  
Kanupriya Sharma ◽  
Praveen Kumar ◽  
Gaurav Verma
Keyword(s):  
Low Cost ◽  
Emission Spectra ◽  
Spherical Shape ◽  
Luminescent Properties ◽  
Nanocomposite Films ◽  
Present System ◽  
Structure Property ◽  
Chemical Route ◽  
Znse Nanocrystals ◽  
Optical And Luminescent Properties

AbstractThis work presents a systematic study of the effect of ZnSe nanocrystals (NCs) concentration on the optical and luminescent properties of poly N-vinylcarbazole (PVK) polymer nanocomposites. The ZnSe nanocrystals were synthesized by a simple coprecipitation chemical route, while PVK:ZnSe nanocomposite films were fabricated using the spin coating technique. The samples were characterized by XRD, TEM, SEM, UV-Vis and fluorescence techniques. The X-ray diffraction and TEM studies confirmed the particle size, microstructure and spherical shape of the synthesized nanocrystals. The ZnSe nanocrystals in PVK caused a decrease in optical gap with increasing concentration of nanocrystals. The emission spectra exhibited augmentation in intensity up to 70 wt.% of nanoparticles while further addition resulted in a decrease in luminescence. The structure-property relationships obtained for the present system are important for developing low cost illumination devices.

Fabrication and Luminescent Properties of YVO4: Eu3+/MCM-41 Mesoporous Composites

2014 ◽  
Vol 707 ◽  
pp. 102-105
Author(s):  
Yi Jiang ◽  
Su Wen Li
Keyword(s):  
Hydrothermal Method ◽  
Luminescent Properties ◽  
Mesoporous Structure ◽  
Luminescence Properties ◽  
Ordered Mesoporous ◽  
Structure Morphology ◽  
Intrinsic Excitation ◽  
Mesoporous Composites ◽  
Mcm 41

The optical functionalized YVO4: Eu3+/MCM-41 mesoporous composites were prepared by hydrothermal method. The structure, morphology, luminescence properties and fluorescence dynamics were studied systemically. The compared studies of the luminescence properties of YVO4: Eu3+/MCM-41 with YVO4: Eu3+ nanocrystal were performed. The results show that the YVO4: Eu3+/MCM-41 retains high ordered mesoporous structure of MCM-41. In YVO4: Eu3+/MCM-41, the intrinsic excitation bands of Eu3+ disappears and the lifetimes of Eu3+ become short. The luminescent efficiency of YVO4: Eu3+/MCM-41 is higher than ones of the YVO4: Eu3+ nanocrystal.

The Influence of ZrO2 Containing 10% Eu 3+ on the Polyurethane Hard Domain Structure in Nanocomposites with Luminescence Properties

2007 ◽  
Vol 128 ◽  
pp. 151-156 ◽  
Author(s):  
Joanna Ryszkowska ◽  
Ewelina Zawadzak ◽  
Piotr Zapart ◽  
Witold Łojkowski ◽  
A. Opalińska ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Analysis ◽  
Domain Structure ◽  
In Situ Polymerization ◽  
Emission Spectra ◽  
Luminescent Properties ◽  
Luminescence Properties ◽  
Hard Domain ◽  
Polyurethane Nanocomposites

This paper presents the results of studies on ZrO2 containing 10% Eu3+ as a nanofiller in polyurethane nanocomposites with luminescent properties. The nanocomposites, which are potential materials for electro-optical-electronic applications, were prepared by in-situ polymerization. Emission spectra, thermodegradation, thermal analysis and mechanical properties of polyurethane ZrO2/10% Eu3+ were investigated and the structure examined using HRSEM. The aim was to investigate the influence of the distribution of nanofillers in the composite and the structure of hard domains of polyurethanes on the relevant properties for opto-electronic applications.

Luminescence Properties of Rare Earth Activated Aluminates Based Phosphor

2016 ◽  
Vol 28 ◽  
pp. 115-119
Author(s):  
Anupam Selot ◽  
Kapil Dev ◽  
Mahendra Aynyas ◽  
Sanjay Bhatt
Keyword(s):  
Emission Spectra ◽  
Combustion Method ◽  
Emission Peak ◽  
Prepared Phosphor ◽  
Ultraviolet Region ◽  
X Ray Diffraction ◽  
Quenching Mechanism ◽  
Strong Emission ◽  
X Ray ◽  
Peak Intensity

A blue emitting phosphor BaAl2O4 doped with Gd3+ were prepared by combustion method at 5000C. The prepared phosphor were investigated by X-ray Diffraction to determine the crystalinity. Photoluminescence emission spectra centred at 369 nm under ultraviolet region, which corresponds to 5d-4f transition of Gd3+ ions. The PL spectra showed strong emission peak intensity and extending to 400nm to 453nm.Concentration quenching mechanism were occurred about 1mol% of Gd3+ ion. The results revealed that phosphor prepared by using combustion method can be useful WLED.

Combustion Synthesis and Luminescence Properties of NaY1-XTbX(WO4)2 Novel Green Phosphors

2011 ◽  
Vol 295-297 ◽  
pp. 861-864
Author(s):  
Xian Hua Qian ◽  
Da Feng Zhang ◽  
Xi Peng Pu
Keyword(s):  
Decay Curve ◽  
Green Light ◽  
Combustion Method ◽  
Luminescence Properties ◽  
Photoluminescence Spectra ◽  
Green Phosphor ◽  
X Ray ◽  
Fluorescent Lamps ◽  
Structure Morphology ◽  
Light Excitation

NaY1-xTbx(WO4)2 green phosphors have been synthesized by a facile combustion method. The structure, morphology and luminescence properties of as-synthesized phosphors were characterized via X-ray powder diffraction (XRD), photoluminescence spectra, and decay curve. The XRD results indicate that as-synthesized phosphors exhibit sheelite-type structure without any impurity phase. The as-obtained phosphors emit strong green light centered at 546 nm under ultraviolet light excitation. The lifetimes are about 0.57 ms. The excellent luminescence properties make it a new promising green phosphor for fluorescent lamps application.

scholarly journals Synthesis, Structure, Morphology, and Luminescent Properties of Ba2MgWO6: Eu3+ Double Perovskite Obtained by a Novel Co-Precipitation Method

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1614 ◽  
Author(s):  
Thi Hong Quan Vu ◽  
Bartosz Bondzior ◽  
Dagmara Stefańska ◽  
Natalia Miniajluk ◽  
Przemysław J. Dereń
Keyword(s):  
Broad Band ◽  
Emission Spectra ◽  
Double Perovskite ◽  
Luminescent Properties ◽  
Precipitation Method ◽  
High Symmetry ◽  
Cation Site ◽  
Structure Morphology ◽  
Co Precipitation ◽  
First Time

Eu3+ doped Ba2MgWO6 (BMW) double-perovskite was successfully synthesized for the first time by the co-precipitation method. The synthesis procedure, crystal structure, as well as morphology of obtained samples are presented. Domination of the 5D0–7F1 magnetic–dipole over forced electric–dipole transitions in the emission spectra indicates that Eu3+ ions are located in the high symmetry site with inversion center. Only one emission line assigned to the 5D0–7F0 transition was observed, confirming that europium substituted for only one host cation site. The photoluminescence excitation (PLE) spectrum is dominated by a strong and broad band related to the O2− → Eu3+ and O2− → W6+ charge transfer. The decay of the emission from the 5D0 and 5D1 levels was investigated. The temperature-dependent emission spectra showed that the T0.5 is equal to 350 K. Extinguishing mechanisms of the Eu3+ luminescence in the studied host are discussed.

Combustion Synthesis of Nanocrystalline Y2O2S: Eu 3+ , Mg 2+ , Ti 4+ Red Long-Lasting Phosphors Using Mixture Fuel of Thiourea and Citric Acid

2013 ◽  
Vol 652-654 ◽  
pp. 669-672 ◽  
Author(s):  
Xiao Bao Han ◽  
Xiang Guo Li ◽  
Gui Hua Peng ◽  
Zhen Hua Liang ◽  
Xia Wang
Keyword(s):  
Citric Acid ◽  
Luminescent Properties ◽  
Combustion Method ◽  
Molar Ratio ◽  
Hexagonal Crystal Structure ◽  
X Ray Diffraction ◽  
Hexagonal Crystal ◽  
Red Emission ◽  
X Ray ◽  
Structure Morphology

Nanocrystalline Y2O2S: Eu3+, Mg2+, Ti4+red long-lasting phosphor was synthesized successfully by combustion method using thiourea and citric acid as fuel. The structure, morphology and luminescent properties of these phosphors were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence spectroscopy (PL). The experimental results revealed that the phosphor was composed of sheet-shaped Y2O2S with hexagonal crystal structure. They exhibited strong red emission at 617 nm and 626nm. In addition, the dosage of citric acid has great effect on the phosphor. When molar ratio of citric acid to Y3+is 1.3, the resulted phosphor gives the highest emission intensity.

Luminescent Properties of Eu3+-Doped HfO2 Powders Prepared by Combustion

2010 ◽  
Vol 434-435 ◽  
pp. 805-807 ◽  
Author(s):  
Jing Meng ◽  
Dan Yu Jiang ◽  
Qiang Li
Keyword(s):  
High Energy Physics ◽  
Raw Materials ◽  
Flaw Detection ◽  
Emission Spectra ◽  
Luminescent Properties ◽  
Combustion Method ◽  
High Energy ◽  
Host Lattice ◽  
Cubic Phase ◽  
Mixed Solution

Scintillators are ideal candidates used in detectors for X-ray ,γ-ray and high energy ray , and have been widely applied in nuclear medicine , high energy physics ,geologic survey , security inspection and material flaw detection. The high density of HfO2 is an attractive compound for host lattice activated by rare earth for applications as scintillating materials. This paper reported the synthesis of Eu3+ doped HfO2 nanopowders by chemical self-combustion method at low temperature. Analytical grade Eu(NO3)3 and high pure HfOCl2 were used as raw materials. The requisite amount of urea and glycine as the mixed fuel were added to the mixed solution. A little EDTA was used as a complexant. The mixed solution was dried at 200°C, and fired at 450°C. The powders synthesized by self-combustion were then calcined at 800°C to profit the crystal growth and improve the luminescent properties. XRD, TEM were employed to analyze the phase composition and the characteristics of as-obtained powders. The TEM images display typical nano-structured morphology of Eu3+ doped HfO2. Analysis of XRD indicates that Eu3+ doped HfO2 nanopowders are cubic phase. The excitation and emission spectra were analyzed by the fluorescence photometer. There are two peaks in emission spectra .One is at 595nm, and another is at 614nm. The luminescent properties also reveal the structure of cubic phase.

Effect of Bi3+ ion concentration on crystal structure and luminescent properties of blue–green-emitting Y2O3:Bi3+ phosphors

2020 ◽  
Vol 13 (07) ◽  
pp. 2050036
Author(s):  
Qian Li ◽  
Biao Zhang ◽  
Zhilei Wei ◽  
Miao He ◽  
Hailong Wang ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Emission Spectra ◽  
Luminescent Properties ◽  
Combustion Method ◽  
Ion Concentration ◽  
Solution Combustion ◽  
Solution Combustion Method ◽  
Light Emitting ◽  
Broadband Emission ◽  
White Light Emitting Diodes

Blue–green-emitting Y2O3 : [Formula: see text]Bi[Formula: see text] ([Formula: see text] = 0.25–1.50 mol.%) phosphors were synthesized by a solution combustion method followed by high temperature annealing. The effect of Bi[Formula: see text] ion concentration on the crystal structure and photoluminescence performance of the phosphors were investigated. The results show that the cell parameter and cell volume of Y2O3host were increased with the Bi[Formula: see text] concentration, and all the phosphor powders exhibited porous lamellar structure with the width of [Formula: see text]500 nm. The emission spectra of the phosphors ([Formula: see text] = 335 nm) consist of three broadband emission spectra centered at 370 nm (3A[Formula: see text]A[Formula: see text], 410 nm (3E[Formula: see text]A[Formula: see text] and 486 nm (3B [Formula: see text]A), respectively. The phosphor exhibited the optimal luminescence performance at [Formula: see text]= 0.50% and the dipole–dipole and quadrupole–quadrupole interactions among Bi[Formula: see text] ions could lead to the concentration quenching. The color coordinates of Y2O3:0.50%Bi[Formula: see text] were (0.1595, 0.2250), indicating that the as-synthesized blue–green phosphors have a broad application prospect in the field of white light-emitting diodes.

Hydrothermal Synthesis and Luminescent Properties of Spherical LaPO4:Ln3+ (Ln3+= Eu3+, Dy3+, Ce3+, Tb3+)

2015 ◽  
Vol 1120-1121 ◽  
pp. 396-400 ◽  
Author(s):  
Jie Dai ◽  
Guo Chao Li ◽  
Meng Lv ◽  
Rui Sen Zhou ◽  
Xia Li
Keyword(s):  
Emission Spectra ◽  
Luminescent Properties ◽  
Flat Panel Displays ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
Strong Light ◽  
X Ray ◽  
Ultraviolet Excitation ◽  
Structure Morphology ◽  
Potential Applications

Uniform LaPO4 and LaPO4:Ln3+ (Ln3+= Eu3+, Dy3+, Ce3+, Tb3+) microspheres have been selectively synthesized via a hydrothermal route, without using any catalyst, or template. X-ray diffraction, SEM, TEM, and photoluminescence spectroscopy were used to characterize the phase structure, morphology, and luminescence properties of the as-prepared samples. SEM results indicate that as-obtained samples have perfect spherical morphology with narrow size distribution. PL excitation and emission spectra demonstrated the LaPO4:Ln3+ phosphors show strong light emissions with different colors coming from different activator ions under ultraviolet excitation, which might find potential applications in fields such as light phosphor powders and advanced flat panel displays.

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