Quantum simulation of the yellow emission band of CsXe

Ti,Eu co-doped Y2O2S:0.06Ti,0.08Eu phosphor with red long afterglow emission from Eu ions was synthesized via traditional sintering method. Results showed that sintering temperature has great influence on the crystal structure, luminescence and afterglow property of the phosphors. The best luminescence and afterglow properties were obtained for the phosphors sintered at 1200°C for 2.5h. Furthermore, only emissions originated from charge transition of Eu3+ was found in the luminescence spectra whereas the afterglow spectra were composed of two sets of emissions: a broad yellow emission band around 565nm and a group of narrow peaks in the wavelength range above 530 nm. The origin of afterglow spectra was discussed: the former is likely related to emission from Ti related traps and the latter is supposed to come from the Eu3+ through an energy transfer process from Ti emission to Eu3+.

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Yellow Emission Obtained by Combination of Broadband Emission and Multi-Peak Emission in Garnet Structure Na2YMg2V3O12: Dy3+ Phosphor

Molecules ◽

10.3390/molecules25030542 ◽

2020 ◽

Vol 25 (3) ◽

pp. 542 ◽

Cited By ~ 3

Author(s):

Weiyi Zhang ◽

Can He ◽

Xiaowen Wu ◽

Ximing Huang ◽

Fankai Lin ◽

...

Keyword(s):

Solid State ◽

White Light ◽

Emission Band ◽

Uv Light ◽

Light Emitting Diode ◽

Color Temperature ◽

Broad Emission Band ◽

Yellow Emission ◽

Conventional Solid State Reaction ◽

Broad Emission

The fabrication and luminescent performance of novel phosphors Na2YMg2V3O12:Dy3+ were investigated by a conventional solid-state reaction method. Under near-UV light, the Na2YMg2V3O12 host self-activated and released a broad emission band (400–700 nm, with a peak at 524 nm) ascribable to charge transfer in the (VO4)3− groups. Meanwhile, the Na2YMg2V3O12:Dy3+ phosphors emitted bright yellow light within both the broad emission band of the (VO4)3- groups and the sharp peaks of the Dy3+ ions at 490, 582, and 663 nm at a quenching concentration of 0.03 mol. The emission of the as-prepared Na2YMg2V3O12:Dy3+ phosphors remained stable at high temperatures. The obtained phosphors, commercial Y2O3:Eu3+ red phosphors, and BaMgAl10O17:Eu2+ blue phosphors were packed into a white light-emitting diode (WLED) device with a near-UV chip. The designed WLED emitted bright white light with good chromaticity coordinates (0.331, 0.361), satisfactory color rendering index (80.2), and proper correlation to a color temperature (7364 K). These results indicate the potential utility of Na2YMg2V3O12:Dy3+ phosphor as a yellow-emitting phosphor in solid-state illumination.

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A New Salt-Inclusion Single-Phased White Phosphor Ba7B3SiO13Br:Dy3+ for White Light-Emitting Diodes

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.803.93 ◽

2019 ◽

Vol 803 ◽

pp. 93-97

Author(s):

Hai Dong Ju ◽

Bao Ling Wang ◽

Qi Mei Yang

Keyword(s):

White Light ◽

Emission Band ◽

Light Emitting Diodes ◽

Hexagonal Phase ◽

Blue Emission ◽

Yellow Emission ◽

Conventional Solid State Reaction ◽

Blue Emission Band ◽

Light Emitting ◽

White Light Emitting Diodes

A series of Ba7B3SiO13Br:Dy3+ phosphors were synthesized by a conventional solid-state reaction method for the first time. The X-ray diffraction patterns confirmed that the samples were pure phase and crystallized in a hexagonal phase with a space group of the P63mc (186). The luminescence spectrum exhibited a strong blue emission band peaked at 478 nm, a strong yellow emission band at 575 nm and a weak emission band at 665 nm, corresponding to the transitions from 4F9/2 to 6H15/2, 6H13/2 and 6H13/2 of Dy3+, respectively. According to the emission spectrum of Ba6.92B3SiO13Br:0.08Dy3+ excited at 349 nm, the chromaticity coordinate was calculated to be (0.317, 0.358) located on the white light region. The concentration quenching mechanism of Dy3+ in Ba7B3SiO13Br was ascribed to the multipolar-multipolar interaction. The current researches suggested that the phosphor can be used as a white phosphor suitable for white light-emitting diodes.

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Crystal structure and pale-yellow emitting properties of K3Gd1–x Dy x B6O12 solid solutions

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229619013305 ◽

2019 ◽

Vol 75 (11) ◽

pp. 1494-1501 ◽

Cited By ~ 1

Author(s):

Rui-Juan Zhang ◽

Jian-Chao Shi ◽

Dan-Dan Zhao ◽

Xiao-Yang Han ◽

Ling Deng ◽

...

Keyword(s):

Three Dimensional ◽

Yellow Emission ◽

Molten Salt Method ◽

X Ray Diffraction ◽

Pale Yellow ◽

Ft Ir ◽

Fourier Transform Ir ◽

The Fourier Transform ◽

Uv Excitation ◽

Yellow Emission Band

A new potassium dysprosium polyborate, K3DyB6O12, has been prepared via the high-temperature molten salt method and structurally characterized by single-crystal X-ray diffraction analysis. The structure can be described as a three-dimensional framework composed of isolated bicyclic [B5O10]5− groups and Dy3+ and K+ ions. The Fourier transform IR (FT–IR) and ultraviolet–visible (UV–Vis) spectra were investigated. A series of K3Gd1–x Dy x B6O12 phosphors was prepared and their photoluminescence properties were studied. The K3Gd1–x Dy x B6O12 phosphors exhibit a strong yellow emission band at 577 nm (the 4F9/2→6H13/2 transition of Dy3+) under UV excitation of 275 nm (the 8S7/2→6I J transition of Gd3+), suggesting the occurrence of the energy transfer Gd3+→Dy3+. The optimized doping concentration of the Dy3+ ion was 8 mol%. We may expect that K3Gd1–x Dy x B6O12 is a promising pale-yellow emission phosphor for visual displays or solid-state lighting.

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Defect structure and luminescence behaviour of agate — results of electron paramagnetic resonance (EPR) and cathodoluminescence (CL) studies

Mineralogical Magazine ◽

10.1180/002646199548394 ◽

1999 ◽

Vol 63 (2) ◽

pp. 149-163 ◽

Cited By ~ 46

Author(s):

J. Götze ◽

M. Plötze ◽

H. Fuchs ◽

D. Habermann

Keyword(s):

Emission Band ◽

Defect Density ◽

Volcanic Rocks ◽

Trace Element Analysis ◽

Yellow Emission ◽

Supersaturated Solution ◽

High Concentration ◽

Element Analysis ◽

Blue Band ◽

Paramagnetic Resonance

AbstractSamples of agate and quartz incrustations from different parent volcanic rocks of certain world-wide localities were investigated by EPR, CL and trace element analysis. In all agate samples the following paramagnetic centres were detected:, E′1, [AlO4]0 [FeO4/M+]0 and [GeO4/M+]0. Centres of the type [TiO4/Li+]0 and [TiO4/H+]0, which were detected in quartz of the parent volcanics, are absent in agate. Generally, the abundance of centres (silicon vacancy) and E′1 centres (oxygen vacancy) in agate is remarkably higher than in quartz. The high defect density in agates points to rapid growth of silica from a strongly supersaturated solution probably with a noncrystalline precursor.CL microscopy reveals internal structures and zoning in agates and quartz incrustations which clearly differ from those discernible by conventional polarizing microscopy. The CL spectra of agates differ from those of quartz from crystalline rocks. At least three broad emission bands were detected in the CL spectra: a blue band of low intensity, a yellow band at about 580 nm, and an intense red band at 650 nm. The CL emission at 650 nm shows some relations to the hydroxyl or alkali content and the abundance of centres and E′1 centres. The emission intensity increases during electron bombardement due to the conversion of different precursors (e.g. ≡Si-O-H, ≡Si-O-Na groups) into hole centres. Another conspicuous feature in the CL spectra of agates is the existence of a yellow emission band centred at around 580 nm. The predominance of the yellow CL emission band and the high concentration of E′1 centres are typical for agates of acidic volcanics and are indicative of a close relationship between the two.

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Crystal Structure and Photophysical Properties of a Novel Dy-Hg Isonicotinic Acid Compound with One-Dimensional Chain-Like Cations

Acta Chimica Slovenica ◽

10.17344/acsi.2020.5921 ◽

2020 ◽

Vol 67 (4) ◽

pp. 1111-1117

Author(s):

Wen-Tong Chen

Keyword(s):

Crystal Structure ◽

Solid State ◽

Emission Band ◽

Hydrothermal Reaction ◽

Isonicotinic Acid ◽

Photophysical Properties ◽

Diffuse Reflectance Spectrum ◽

Yellow Emission ◽

Monoclinic System ◽

One Dimensional

A novel Dy-Hg compound [Dy(HIA)3(H2O)2]2n · 2nHgCl4 · nHgCl5 · nH3O · 3nH2O (1; HIA = isonicotinic acid) was prepared through a hydrothermal reaction and characterized by X-ray diffraction. The compound crystallizes in the space group of C2/c of the monoclinic system. The crystal structure of compound 1 has one-dimensional (1-D) chain-like cations. A photoluminescence experiment with a solid-state sample revealed that this compound exhibits a yellow emission band at 575 nm and, this emission band shall come from the 4f electron 4F9/2 → 6H13/2 characteristic transfer of Dy3+ ions. The compound features CIE chromaticity coordinates of 0.5168 and 0.4824 in the yellow region. A UV-visible diffuse reflectance spectrum with a solid-state sample unveiled that this compound possesses a wide optical band gap of 3.39 eV.

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The Fabrication of Ag Islands on AlN/GaN/AlN/Si(111) by Using Thermal Evaporator and Thermal Annealing Methods

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.364.327 ◽

2011 ◽

Vol 364 ◽

pp. 327-332 ◽

Cited By ~ 1

Author(s):

Mohd Zaki Mohd Yusoff ◽

А. Mahyuddin ◽

Hassan Zainuriah ◽

Abu Hassan Haslan ◽

Mat Johar Abdullah ◽

...

Keyword(s):

Yellow Emission ◽

Band Edge Emission ◽

Electrical Characteristics ◽

X Ray Diffraction ◽

Edge Emission ◽

X Ray ◽

Treated Sample ◽

Thermal Evaporator ◽

Yellow Emission Band

In this paper, we studied growth of AlN/GaN/AlN on Si (111) by using plasma assisted molecular beam epitaxy (PA-MBE) system. The structural and optical characteristics of the sample have been investigated by using high resolution X-ray diffraction (HR-XRD), Raman spectroscopy and photoluminescence (PL). PL spectrum of the sample has shown sharp and intense band edge emission of GaN with the absence of yellow emission band, indicating good crystal quality of the sample. The silver (Ag) metal contact was then deposited on the sample followed by thermal treatment at 500°C and 700°C, respectively. Treated sample at 700°C showed good spherical Ag islands on sample compared to the treated sample at 500°C. The effect of Ag islands on the electrical characteristics of sample was also examined by usingI-Vmeasurement. The results showed that the treated sample at 700°C has decreased the photo-current of Schottky diode.

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