Effect of alkali charge compensator on luminescent properties in Eu3+ doped β-dicalcium silicate

Red phosphors CaMoO4:Eu3+ were synthesized by microwave method with MnO2 as microwave absorbent. The phase structure and luminescent properties of the as-synthesized phosphors were investigated by X-ray powder diffraction and Fluorescence spectrophotometer. The results show that when the reaction time was 40 min, microwave power was medium-high fire (~560 W), we got the tetragonal CaMoO4:Eu3+ pure phase. The excitation spectrum of CaMoO4:Eu3+ was composed by a broad band between 200 nm and 350 nm and a series of peaks from 350 nm to 500 nm. The main peak was at 305 nm. The emission spectrum was composed of a series of peaks in the range of 550~750 nm and the main peak was at 617 nm due to the 5D0→7F2 transition of Eu3+. Doping charge compensator Li+, Na+ or K+ could improve the luminous intensity of the sample. When the doping amount of Li+, Na+ or K+ were 8 mol%, the luminous intensity of the sample reached the maximum. The intensity of the emission peak at 617 nm was 4.04, 3.42, 3.48 times of sample without doping charge compensator.

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Low temperature synthesis of SrS:Ce phosphor by carbothermal reduction method: Influence of sulfur and charge compensator on the luminescent properties

Materials Research Bulletin ◽

10.1016/j.materresbull.2006.07.010 ◽

2007 ◽

Vol 42 (4) ◽

pp. 753-761 ◽

Cited By ~ 10

Author(s):

P. Thiyagarajan ◽

M. Kottaisamy ◽

M.S. Ramachandra Rao

Keyword(s):

Low Temperature ◽

Carbothermal Reduction ◽

Reduction Method ◽

Luminescent Properties ◽

Low Temperature Synthesis ◽

Temperature Synthesis ◽

Carbothermal Reduction Method ◽

Charge Compensator

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Effect of doping charge compensator Li+ on structure and luminescent properties of ZnWO4: Eu3+, Dy3+ phosphor

Optik ◽

10.1016/j.ijleo.2019.163056 ◽

2019 ◽

Vol 194 ◽

pp. 163056 ◽

Cited By ~ 2

Author(s):

Yongqing Zhai ◽

Qinglin Sun ◽

Longtai Jiang ◽

Weiao Wang ◽

Xiangyun Chen ◽

...

Keyword(s):

Luminescent Properties ◽

Charge Compensator ◽

Effect Of Doping

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Luminescent Properties of a Novel Red-Emitting Phosphor Ca1.95P2O7:0.05Eu3+, B3+, M+ (M=Li, Na, K) for White Light-Emitting Diodes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.2481 ◽

2013 ◽

Vol 634-638 ◽

pp. 2481-2484 ◽

Cited By ~ 2

Author(s):

Mi Fang Yan ◽

Li Hong Xue ◽

You Wei Yan

Keyword(s):

Boric Acid ◽

Synthesis Method ◽

Emission Spectra ◽

Luminescent Properties ◽

Emission Peak ◽

Molar Ratio ◽

Light Emitting ◽

Charge Compensator ◽

White Light Emitting Diodes ◽

Red Emitting Phosphor

A series of Ca1.95P2O7:0.05Eu3+, B3+, M+ (M=Li, Na, K) phosphors were prepared by combustion synthesis method using boric acid as flux and M+ as charge compensator. The crystal structure and luminescent properties were investigated. The emission spectra show that the most intensive emission peak is located at 612nm, corresponding to the 5D0-7F2 transition of Eu3+. The phosphors can be efficiently excited by 394nm and 464nm light, which are matched well with the emission wavelength of near UV and blue light-emitting chips, respectively. The results show that boric acid is effective in improving the luminescence intensity, and the optimum molar ratio of boric acid to the pyrophosphate is 0.09. The relative emission intensities of Eu3+ (5D0-7F2) in Ca2P2O7:Eu3+ phosphors with M+ (M=Li, Na, K) introduced as charge compensator are significantly enhanced, and the phosphor added with Na+ show the strongest emission.

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Concentration Dependence of Luminescent Properties forSr2TiO4:Eu3+Red Phosphor and Its Charge Compensation

Journal of Nanomaterials ◽

10.1155/2012/698434 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 12

Author(s):

Zhou Lu ◽

Le Zhang ◽

Lixi Wang ◽

Qitu Zhang

Keyword(s):

Red Light ◽

Luminescent Properties ◽

Charge Compensation ◽

Red Phosphor ◽

White Leds ◽

Structure Damage ◽

Charge Compensator ◽

Composition Structure ◽

Cie Chromaticity ◽

Light Color

Sr2TiO4:Eu3+phosphors using M+(M = Li+, Na+, and K+) as charge compensators were prepared by the solid-state reaction. The powders were investigated by powder X-ray diffraction (XRD) and photoluminescence spectra (PL) to study the phase composition, structure, and luminescent properties. The results showed that Li+ion was the best charge compensator. The phase was Sr2TiO4when the doping concentration was small (x≤10.0%). Whenxreached 15.0%, the phase turned into Sr3Ti3O7because of the structure damage. The phosphor could be effectively excited by ultraviolet (365, 395 nm) and blue light (465 nm), and thenitemitted intense red light that peaked at around 620 nm (5D0→7F2). In addition, the emission of 700 nm (5D0→7F4) enhanced the red light color purity. The CIE chromaticity coordinates of samples with the higher red emission were between (0.650, 0.344) and (0.635, 0.352). Doped layered titanate Sr2TiO4:Eu3+is a promising candidate red phosphor for white LEDs which can be suited for both near-UV LED chip and blue LED chip.

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Enhancement of the red emission in Ba3(PO4)2:Eu3+ by addition of charge compensator Na+

Modern Physics Letters B ◽

10.1142/s0217984918400638 ◽

2018 ◽

Vol 32 (34n36) ◽

pp. 1840063 ◽

Cited By ~ 1

Author(s):

Dandan Zhang ◽

Huaxing Xiao ◽

Wei Jiang ◽

Xia Cao ◽

Lu Huang ◽

...

Keyword(s):

Crystal Structure ◽

Solid State ◽

Red Light ◽

Emission Spectra ◽

Luminescent Properties ◽

Host Crystal ◽

Red Emission ◽

Uv Led ◽

Charge Compensator ◽

Red Emitting Phosphor

Ba[Formula: see text](PO4)2:0.04Eu[Formula: see text] (S1) and Ba[Formula: see text]Na[Formula: see text](PO4)2:0.04Eu[Formula: see text] (S2) were prepared by solid state reaction. The phases and luminescent properties of the obtained phosphors were characterized. The results demonstrate that the phosphors particles emit an intensive red light under excitation at 395 nm. Both phosphors can be efficiently excited by ultraviolet and blue light, and the emission spectra mainly consist of two emission peaks at 591 nm and 611 nm. The crystallographic sites of Eu[Formula: see text] ions in Ba3(PO4)2 host were discussed on the base of emission spectra and its host crystal structure. By introducing the charge compensator Na[Formula: see text] into the S1 phosphor, its emission intensity was enhanced, indicating that S2 could serve as a promising red-emitting phosphor for UV LED applications.

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Microstructural characterization of laser-melted/roller-quenched dicalcium silicate

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104972 ◽

1988 ◽

Vol 46 ◽

pp. 582-583

Author(s):

C. J. Chan ◽

K. R. Venkatachari ◽

W. M. Kriven ◽

J. F. Young

Keyword(s):

Particle Size ◽

Raw Materials ◽

Shape Change ◽

Microstructural Characterization ◽

Particle Size Effect ◽

Dicalcium Silicate ◽

Laser Melting ◽

Uniform Size ◽

Cell Shape Change ◽

Wide Range

Dicalcium silicate (Ca2SiO4) is a major component of Portland cement. It has also been investigated as a potential transformation toughener alternative to zirconia. It has five polymorphs: α, α'H, α'L, β and γ. Of interest is the β-to-γ transformation on cooling at about 490°C. This transformation, accompanied by a 12% volume increase and a 4.6° unit cell shape change, is analogous to the tetragonal-to-monoclinic transformation in zirconia. Due to the processing methods used, previous studies into the particle size effect were limited by a wide range of particle size distribution. In an attempt to obtain a more uniform size, a fast quench rate involving a laser-melting/roller-quenching technique was investigated.The laser-melting/roller-quenching experiment used precompacted bars of stoichiometric γ-Ca2SiO4 powder, which were synthesized from AR grade CaCO3 and SiO2xH2O. The raw materials were mixed by conventional ceramic processing techniques, and sintered at 1450°C. The dusted γ-Ca2SiO4 powder was uniaxially pressed into 0.4 cm x 0.4 cm x 4 cm bars under 34 MPa and cold isostatically pressed under 172 MPa. The γ-Ca2SiO4 bars were melted by a 10 KW-CO2 laser.

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