Effect of Annealing Treatments on Optical and Luminescence Properties of Lu1.8Y0.2SiO5:Ce Single Crystal

LYSO:Ce crystal is one of efficient scintillation materials with high light output and short decay time. LYSO:Ce crystal grown by Czochralski method can be affected by annealing treatments. In present work, annealing treatments in different atmosphere (air, N2 and H2) were carried out on the LYSO:Ce crystals to investigate the effect on the optical and luminescence properties after annealing. The optical transmittance, excitation and emission spectrum, and the decay time have been attained at room temperature. Luminescence efficiency has been presented by the integrated area of emission spectra under ultraviolet (UV) excitation. It is found that annealing treatments almost do not affect the optical transmittance. Annealing in N2 atmosphere has no noteworthy effect on the luminescence intensity of LYSO:Ce crystals, but increases much annealing in H2 atmosphere, dramatically decreases the luminescence intensity after annealing in air. In addition, the decay time of LYSO:Ce crystals are affected by annealing treatment either in air or in H2 atmosphere.

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Luminescence properties of novel red-emitting phosphor InNb1-xPxO4:Eu3+ for white light emitting-diodes

Materials Science-Poland ◽

10.1515/msp-2015-0050 ◽

2015 ◽

Vol 33 (2) ◽

pp. 331-334 ◽

Cited By ~ 1

Author(s):

An Tang ◽

Tao Ma ◽

Liduo Gu ◽

Yongtao Zhao ◽

Junhui Zhang ◽

...

Keyword(s):

White Light ◽

Luminescence Intensity ◽

Light Emitting Diodes ◽

Red Light ◽

Emission Spectra ◽

Luminescence Properties ◽

Potential Candidate ◽

Light Emitting ◽

Near Ultraviolet ◽

White Light Emitting Diodes

AbstractInNb1-xPxO4:Eu3+ red phosphors were synthesized by solid-state reaction and their luminescence properties were also studied through photoluminescence spectra. The excitation and emission spectra make it clear that the as-prepared phosphors can be effectively excited by near-ultraviolet (UV) 394 nm light and blue 466 nm light to emit strong red light located at 612 nm, due to the Eu3+ transition of 5D0 → 7F2. The luminescence intensity is dependent on phosphorus content, and it achieves the maximum at x = 0.4. Excessive phosphorus in the phosphors can result in reduction of luminescence intensity owing to concentration quenching.With the increasing content of phosphorus, the phosphors are prone to emit pure red light. This shows that the InNb1.6P0.4O4:0.04Eu3+ phosphor may be a potential candidate as a red component for white light emitting-diodes.

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Luminescence Properties of Tm3+ /Dy3+ Co-Doped Zinc-Aluminum Phosphate Glasses for White LED

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.602-604.821 ◽

2012 ◽

Vol 602-604 ◽

pp. 821-828 ◽

Cited By ~ 1

Author(s):

C.T. Lin ◽

S.W. Yung ◽

J. Lin ◽

W.S. Chen ◽

C.H. Lai ◽

...

Keyword(s):

Light Emission ◽

Emission Spectra ◽

Aluminum Phosphate ◽

Phosphate Glasses ◽

Oscillator Strengths ◽

Luminescence Properties ◽

Excitation Wavelength ◽

Intensity Parameters ◽

Uv Excitation ◽

Co Doped

Tm3+ and Dy3+ co-doped zinc-aluminum phosphate glasses were prepared in this study. Judd-Ofelt theory has been used to evaluate the three intensity parameters Ω2, Ω4 and Ω6 form the experimental oscillator strengths. The luminescence properties were investigated by excitation and emission spectra. White light emission could be induced by combined blue and yellow bands under UV excitation, and the variety of excitation wavelength could change the luminescence color.

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Synthesis and Luminescence Properties of Ba3Y1-xEuxB3O9 (0.05≤x≤0.35) under UV Excitation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.906.60 ◽

2014 ◽

Vol 906 ◽

pp. 60-65 ◽

Cited By ~ 1

Author(s):

Xiao Xia Li

Keyword(s):

Particle Size ◽

Single Phase ◽

Charge Transfer Band ◽

Emission Spectra ◽

Hexagonal Structure ◽

Luminescence Properties ◽

Excitation Energies ◽

Excitation Spectra ◽

X Ray ◽

Uv Excitation

Single phase of Ba3Y1-xEuxB3O9 (0.05 ≤ x≤ 0.35)samples was prepared by the solid state reaction. The crystal structure, the surface, the particle size and luminescence properties were characterized by X-ray diffractometer, scanning electron microscopy and spectrophotometer. The results showed that the obtained samples with the particle size from 0.3 to 1.5 um were hexagonal structure. Monitored by 592 nm emission, the excitation spectra of Ba3Y1-xEuxB3O9were dominated by the charge transfer band of O2-→Eu3+ peaking at about 259 nm until x= 0.15; the transition from 7F0 to 5L6 level of Eu3+ at about 395 nm was maximum after x> 0.15. The strongest emission peak due to the 5D0→7F1transition of Eu3+ was all located at about 592 nm in the emission spectra of Ba3Y1-xEuxB3O9, and the maximum emission was obtained at x= 0.15 and 0.3 under 254 and 395 nm excitation, respectively. The excitationprocess under the two excitation energies was analyzed. It indicated that only the centrosymmetric lattices could be excited under 254 nm excitation; both the centrosymmetric and noncentrosymmetric positions could be excited by 395 nm, accordingly, the ratio of the red emission (5D0→7F2) to the orange one (5D0→7F1) increased, leading to a better chromaticity of the phosphors.

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Crystal Phase, Shape and Luminescence Properties of LaPO4:Eu3+ Nanocrystals

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.166 ◽

2008 ◽

Vol 8 (7) ◽

pp. 3458-3464 ◽

Cited By ~ 19

Author(s):

Pushpal Ghosh ◽

Amitava Patra

Keyword(s):

Growth Mechanism ◽

Decay Time ◽

Luminescence Intensity ◽

Monoclinic Phase ◽

Photoluminescence Property ◽

Oriented Attachment ◽

Crystal Phase ◽

Luminescence Properties ◽

Photoluminescence Properties ◽

Drastic Increase

We demonstrated the change of shape and crystal phase of LaPO4:Eu3+ nanomaterials by tuning the temperature of heating. The mechanism related to morphology control of LaPO4:Eu nanorods/nanoparticles are proposed and discussed. We describe the "oriented attachment" growth mechanism for nanorod-to-nanoparticles transformation with increasing the temperature of heating. It is found that the photoluminescence properties of LaPO4:Eu3+ nanostructures are sensitive to the crystal phase and shape. The drastic increase in luminescence intensity (12 times) and decay time increases from 2.66 to 3.34 ms with changing the shape (nanorod to nanoparticle) and crystal phase (hexagonal to monoclinic phase) for the samples prepared by emulsion based method. Our analysis suggests that the manipulation of the photoluminescence property can be done by changing the crystal phase of nanomaterials.

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Review—Temperature Dependence of Luminescence Intensity and Decay Time in Mn4+-Activated Fluoride and Oxyfluoride Phosphors

ECS Journal of Solid State Science and Technology ◽

10.1149/2162-8777/abe0af ◽

2021 ◽

Vol 10 (2) ◽

pp. 026002

Author(s):

Sadao Adachi

Keyword(s):

Temperature Dependence ◽

Decay Time ◽

Luminescence Intensity

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Annealing effects on luminescent properties of Eu3+ doped Gd2Zr2O7 nanopowders

Science of Sintering ◽

10.2298/sos1503269r ◽

2015 ◽

Vol 47 (3) ◽

pp. 269-272 ◽

Cited By ~ 4

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.

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Люминофоры холодного голубого излучения на основе оксида алюминия, допированного диспрозием

Физика твердого тела ◽

10.21883/ftt.2022.01.51837.196 ◽

2022 ◽

Vol 64 (1) ◽

pp. 95

Author(s):

И.В. Бакланова ◽

В.Н. Красильников ◽

А.П. Тютюнник ◽

Я.В. Бакланова

Keyword(s):

Crystal Structure ◽

Phase Composition ◽

Diffraction Analysis ◽

Powder Diffraction ◽

Thermal Quenching ◽

Emission Spectra ◽

X Ray ◽

White Emission ◽

Uv Excitation ◽

Quenching Of Luminescence

Al2О3:Dy3+ oxides with different colors luminescence were synthesized using precursor technology. The phase composition and crystal structure of the obtained materials were established by X-ray powder diffraction analysis. The excitation and emission spectra, decay curves, thermal quenching of luminescence were studied. Under UV excitation, the phosphors exhibit blue, purplish blue, white emission depending on the concentration of dysprosium and the temperature of annealing of the Al1-xDyx(OH)(HCOO)2 precursor in air.

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Highly Deep Ultraviolet–Transparent h-BN Film Deposited on an Al0.7Ga0.3N Template by Low-Temperature Radio-Frequency Sputtering

Materials ◽

10.3390/ma12244046 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4046

Author(s):

Guo-Dong Hao ◽

Manabu Taniguchi ◽

Shin-ichiro Inoue

Keyword(s):

Low Temperature ◽

Radio Frequency ◽

Hexagonal Boron Nitride ◽

Annealing Treatment ◽

Optical Transmittance ◽

Hexagonal Structure ◽

Light Transmittance ◽

Radio Frequency Sputtering ◽

Deep Ultraviolet ◽

Deposition Processes

Hexagonal boron nitride (h-BN) is an attractive wide-bandgap material for application to emitters and detectors operating in the deep ultraviolet (DUV) spectral region. The optical transmittance of h-BN in the DUV region is particularly important for these devices. We report on the deposition of thick h-BN films (>200 nm) on Al0.7Ga0.3N templates via radio-frequency sputtering, along with the realization of ultrahigh transmittance in the DUV region. The fraction of the gas mixture (Ar/N2) was varied to investigate its effects on the optical transmittance of BN. DUV light transmittance of as high as 94% was achieved at 265 nm. This value could be further enhanced to exceed 98% by a post-annealing treatment at 800 °C in a N2 ambient for 20 min. The phase of the highly DUV–transparent BN film was determined to be a purely hexagonal structure via Raman spectra measurements. More importantly, these deposition processes were performed at a low temperature (300 °C), which can provide protection from device performance degradation when applied to actual devices.

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The decay time of N3 luminescence in natural diamond

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1978.0141 ◽

1978 ◽

Vol 362 (1710) ◽

pp. 405-419 ◽

Cited By ~ 39

Keyword(s):

Decay Time ◽

Internal Conversion ◽

Natural Diamond ◽

Excited Electronic State ◽

Radiative Lifetime ◽

Electric Quadrupole ◽

Paramagnetic Resonance ◽

Luminescence Efficiency ◽

Quadrupole Coupling ◽

Electron Paramagnetic

Measurements are reported of the decay time of photoluminescence from the N3 centre: an impurity centre commonly found in natural diamond. The intrinsic decay time at low temperature is found to be 41 ± 1 ns. The decay time is specimen dependent, decreasing with increasing concentrations of pairs of substitutional nitrogen atoms in the diamonds. The data are consistent with an electric dipole, electric-quadrupole coupling of the N3 centres to the nitrogen pairs. In addition, the decay time is reduced by raising the specimen temperature, especially above 450 K. These results are consistent with internal conversion occurring into another excited electronic state of the N3 centre. The properties required for this state agree with deductions from other optical and electron paramagnetic resonance (e. p. r.) data. The radiative lifetime of the N3 luminescence transition is estimated at 150 ns, in agreement with previous luminescence efficiency measurements.

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