Synthesis and luminescence properties of CaLaMgNbO6:Mn4+ red phosphor for UV-based w-LEDs

A series of [Formula: see text] ([Formula: see text] = 0.0005, 0.001, 0.003, 0.005, 0.007, 0.009) phosphors were prepared by traditional solid-state method at high temperature. The structure and morphology of the samples were analyzed. The results showed that the prepared [Formula: see text] [Formula: see text] phosphors were uniformly dispersed and the particle size was less than 5 [Formula: see text]m. [Formula: see text] phosphors have the strongest excitation peak at 351 nm, which is caused by the [Formula: see text] transition of [Formula: see text] ions. The strongest emission peak is at 697 nm, which is due to the [Formula: see text] level transition of [Formula: see text]. The optimum doping concentration is 0.5 mol.% and the mechanism of concentration quenching is the dipole–dipole interaction between [Formula: see text] ions. Importantly, [Formula: see text] sample has good thermal stability ([Formula: see text]/[Formula: see text] = 48.3%). In addition, the color coordinates of all samples were concentrated in the far-red region (0.733, 0.267). The above results indicate that [Formula: see text] sample has potential application value in the field of white light-emitting diodes ([Formula: see text]-LEDs).

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Synthesis and luminescence properties of new red phosphor YBiW2O9:Eu3+

Functional Materials Letters ◽

10.1142/s1793604717500667 ◽

2017 ◽

Vol 10 (05) ◽

pp. 1750066 ◽

Cited By ~ 3

Author(s):

Zhi Xie ◽

Wang Zhao ◽

Wei-Wei Zhou ◽

Fu-Gui Yang

Keyword(s):

Internal Quantum Efficiency ◽

Solid State Reaction Method ◽

Potential Candidate ◽

Red Phosphor ◽

Light Emitting ◽

Good Thermal Stability ◽

Near Ultraviolet ◽

Chromaticity Coordinate ◽

White Light Emitting Diodes ◽

First Time

A new series of YBiW2O9:Eu[Formula: see text] phosphors were successfully synthesized by the solid-state reaction method for the first time. Pure phase formation of YBiW2O9:Eu[Formula: see text] was confirmed by X-ray powder diffraction. It is found that the 7F[Formula: see text]L6 transition results in the strongest near-ultraviolet excitation centered at 395 nm and the phosphors show strong electric-dipole (ED) transitions (5D[Formula: see text]F[Formula: see text] with red emission peaking at 616[Formula: see text]nm. The optimal Eu[Formula: see text] doping concentration of 70[Formula: see text]mol.% is presented in YBiW2O9:Eu[Formula: see text] phosphors. The Y[Formula: see text]BiW2O9:0.7Eu[Formula: see text] phosphor has better Commission Internationale de l’Eclairage chromaticity coordinate of (0.669, 0.328) in comparison with commercial red-emitting phosphors (Y2O2S:Eu[Formula: see text], Y2O3:Eu[Formula: see text]. The internal quantum efficiency of Y[Formula: see text]BiW2O9:0.7Eu[Formula: see text] was measured to be 45.1%, and temperature-dependent luminescence shows its good thermal stability. All the results suggest that YBiW2O9:Eu[Formula: see text] is a potential candidate of red phosphor for the applications in white light emitting diodes.

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Synthesis and Research of rare earth-doped color tunable Sr3Gd(PO4)3 phosphors

International Journal of Modern Physics B ◽

10.1142/s0217979219502011 ◽

2019 ◽

Vol 33 (18) ◽

pp. 1950201

Author(s):

Boxin Liang ◽

Shuangping Yi ◽

Gengqiao Hu ◽

Zhixiong Fang ◽

Zhengfa Hu

Keyword(s):

Rare Earth ◽

White Light ◽

Dipole Interaction ◽

Critical Distance ◽

Solid State Method ◽

Excitation Peak ◽

Good Thermal Stability ◽

Emission Color ◽

Color Tunable ◽

Rare Earth Doped

Rare earth-doped Sr3Gd(PO4)3 and emission color tunable phosphors Ce[Formula: see text]/Sm[Formula: see text] co-doped Sr3Gd(PO4)3 have been synthesized by a traditional solid-state method. These phosphors were characterized by X-ray diffraction (XRD), FE-SEM, diffuse reflectance spectra (DRS), photoluminescence spectra and lifetime measurements. The quenching concentration of Ce[Formula: see text] ions in Sr3Gd(PO4)3 was about 9 mol.%. An effective energy transfer (ET) from Ce[Formula: see text] ions to Sm[Formula: see text] ions in Sr3Gd(PO4)3 was speculated by the overlapped spectrum for the emission peak of Ce[Formula: see text] and the excitation peak of Sm[Formula: see text] ions. It is demonstrated that the ET mechanism is resonant through the dipole–dipole interaction and the critical distance between Ce[Formula: see text] and Sm[Formula: see text] in Sr3Gd(PO[Formula: see text] is calculated to 15.22 Å. Moreover, Sr3Gd[Formula: see text](PO4)3:0.09Ce[Formula: see text], xSm[Formula: see text] can be adjusted systematically by generating blue light to white light in the CIE diagram which coincide with the ET process of Ce[Formula: see text] ions to Sm[Formula: see text] ions. The Sr3Gd[Formula: see text](PO4)3:0.09Ce[Formula: see text], 0.01Sm[Formula: see text] phosphor also perform at a good thermal stability. All of these experimental results in this work can be served as a potential multicolor tunable phosphor for ultraviolet pumped white light appliance.

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A NEW RED PHOSPHOR OF THE Mn ACTIVATED NON-STOICHIOMETRIC STRONTIUM ALUMINATE 3SrO•5Al2O3 FOR HIGH COLOR RENDERING WHITE LEDS

Functional Materials Letters ◽

10.1142/s1793604713500288 ◽

2013 ◽

Vol 06 (03) ◽

pp. 1350028 ◽

Cited By ~ 1

Author(s):

LEI CHEN ◽

YAO ZHANG ◽

FAYONG LIU ◽

XIAORONG DENG ◽

SHAOCHAN XUE ◽

...

Keyword(s):

Dipole Interaction ◽

Critical Distance ◽

Sem Analysis ◽

Strontium Aluminate ◽

Red Phosphor ◽

Light Emitting ◽

White Leds ◽

Warm White Light ◽

White Light Emitting Diodes ◽

Color Rendering

A new red phosphor of strontium aluminate activated by Mn4+ was developed for high color rendering and warm white light-emitting diodes. The phosphor composition and conditions for synthesis were optimized through solid-state reaction. Meanwhile, the structure and morphology were investigated with XRD and SEM analysis. The results show that the 3SrO•5Al2O3 activated by 0.0005 M Mn fired at 1300°C in air ambient by adopting 2.5 wt.% AlF3 as flux exhibits most efficient luminescence. A white LED device prototype with CIE (0.3291, 0.3571), CCT 5639 K, CRI Ra 92.6, and efficacy 63 lm/W driven at 20 mA has been packaged by pre-coating the red phosphor combined with a yellow one Y3Al5O12:Ce3+ on a blue InGaN chip. The analysis of critical distance and luminescence quench reveal that the mechanism of energy transfer for luminescence is through dipole–dipole interaction.

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Characterization and Photoluminescence of Sr2B2O5:Eu3+, Na+ Red Phosphor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1003.7 ◽

2014 ◽

Vol 1003 ◽

pp. 7-10 ◽

Cited By ~ 1

Author(s):

Li Li Ying ◽

Song Sheng Zheng ◽

Jiang Hui Zheng ◽

Li Han Cai ◽

Chao Chen

Keyword(s):

Uv Light ◽

Dipole Interaction ◽

Solid State Reaction Method ◽

Concentration Quenching ◽

Red Phosphor ◽

Light Emitting ◽

Near Ultraviolet ◽

White Light Emitting Diodes ◽

The Eu ◽

Red Emitting Phosphor

A kind of red emitting phosphor, Sr2B2O5:Eu3+, Na+ for white light-emitting diodes (W-LED) was synthesized by high-temperature solid-state reaction method. The characterization and luminescence properties of the phosphor were investigated. It is found that this phosphor can be effectively excited by 394 nm near-ultraviolet (n-UV) light, and exhibit bright red emission centered at 613 nm corresponding to the 5D0→7F2 transition of Eu3+ ions. It is shown that the 11 mol% of Eu3+ doping concentration in Sr2B2O5:Eu3+, Na+ phosphor is optimum, and the concentration quenching occurs when the Eu3+ concentration is beyond 11 mol%. The concentration quenching mechanism can be interpreted by the dipole–dipole interaction of Eu3+ ions. The present work suggests that this novel phosphor is a kind of potential red emitting phosphor.

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Synthesis and Luminescent Properties of Red Phosphor BaY2O4: Eu3+ for White Light-Emitting Diodes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.811.181 ◽

2013 ◽

Vol 811 ◽

pp. 181-185 ◽

Cited By ~ 1

Author(s):

Lan Tu Ya Wu

Keyword(s):

Sol Gel ◽

Red Light ◽

Emission Spectra ◽

Luminescent Properties ◽

Electric Dipole Transition ◽

Excitation Spectra ◽

Excitation Peak ◽

Red Phosphor ◽

Light Emitting ◽

White Light Emitting Diodes

The rare-earth Eu3+doped BaY2O4red phosphor synthesized by citric acid sol-gel method. The structure, morphology and composition of the red phosphor were characterized by X-ray diffraction, scanning electron microscopy and infrared spectroscopy. The results show that the distribution of the pure phase BaY2O4: Eu3+particles after annealing at 800 °C was irregular, small size of particle is 0.2 μm to 0.4 μm. The excitation spectra of synthesized phosphor at 610 nm monitoring were composed of a broadband and a series of sharp peaks, the strongest excitation peak at 466 nm, the secondly at 395nm. It was indicated that BaY2O4: Eu3+phosphor matching with the widespread applied the output wavelengths of UV LED and blue LED chips. The main emission spectra of samples under blue light excitation is Eu3+ions5D07F2electric dipole transition with a strong red light, so that the BaY2O: Eu3+phosphor may be a better candidate for red component for white LED.

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