Effect of A+ (A = Li, Na and K) co-doping on the luminescence enhancement of CaSr2(PO4)2:Dy3+ phosphors for white light-emitting diodes

Abstract A series of red-emitting phosphors InNbO4:Eu3+,Bi3+ was prepared by a high temperature solid-state reaction. The structure, size distribution and luminescence properties of the phosphors were respectively characterized by X-ray diffraction (XRD), laser particle size and molecular fluorescence spectrometer. The XRD results indicate that the phase-pure samples have been obtained and the crystal structure of the host has not changed under the Eu3+ and Bi3+ co-doping. The test of size distribution shows that the phosphor has a normal size distribution. The excitation spectra illustrate that the dominant sharp peaks are located at 394 nm (7F0→5L6) and 466 nm (7F0→5D2). Meanwhile, the emission spectra reveal that the phosphors excited by the wavelength of 394 nm or 466 nm have an intense red-emission line at 612 nm owing to the 5D0→7F2 transition of Eu3+. Bi3+ doping has not changed the peak positions except the photoluminescence intensity. The emission intensity is related to Bi3+ concentration, and it is up to the maximum when the Bi3+-doping concentration is 4 mol%. Due to good photoluminescence properties of the phosphor, the InNbO4:0.04Eu3+,0.04Bi3+ may be used as a red component for white light-emitting diodes.

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Effect of Partial Ca2+ Substitution with Ln3+ (Ln = Y, La) on Luminescence Enhancement of Ca18.62Zn2(PO4)14:0.38Dy3+ White-Emitting Phosphor for White Light-Emitting Diodes

ACS Applied Electronic Materials ◽

10.1021/acsaelm.1c00622 ◽

2021 ◽

Author(s):

Xue Huang ◽

Teshen Wang ◽

Wentao Zhang ◽

Zhou Zhao ◽

Xiaomeng Wang ◽

...

Keyword(s):

White Light ◽

Light Emitting Diodes ◽

Luminescence Enhancement ◽

Light Emitting ◽

White Light Emitting Diodes

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Luminescence of Tb3Al5O12 phosphors co-doped with Ce3+/Gd3+ for white light-emitting diodes

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.10.123 ◽

2019 ◽

Vol 10 ◽

pp. 1237-1242 ◽

Cited By ~ 4

Author(s):

Yu-Guo Yang ◽

Lei Wei ◽

Jian-Hua Xu ◽

Hua-Jian Yu ◽

Yan-Yan Hu ◽

...

Keyword(s):

White Light ◽

Emission Band ◽

Light Emitting Diodes ◽

Solid State Reactions ◽

Peak Wavelength ◽

Light Emitting ◽

Co Doping ◽

Characteristic Emission ◽

White Light Emitting Diodes ◽

Co Doped

Tb2.96− x Ce0.04GdxAl5O12 phosphors were synthesized through solid-state reactions. The influence of Gd3+ on the luminescence was investigated. Under the excitation at 460 nm, Tb2.96Ce0.04Al5O12 shows the characteristic emission band of Ce3+ with a peak wavelength at about 554 nm. After co-doping Gd3+ into Tb2.96Ce0.04Al5O12, the peak wavelength of the Ce3+ emission band shifts to longer wavelengths, which is induced by the increasing crystal field splitting. However, the Ce3+ emission intensity also decreases because the substitution of Tb3+ with Gd3+ causes lattice deformation and generates numerous structural and chemical defects. By comparing the light parameters of white light-emitting diodes (WLEDs) containing Y2.96Ce0.04Al5O12, Tb2.96Ce0.04Al5O12 and Tb2.81Ce0.04Gd0.15Al5O12 phosphors, we can find that the WLED containing the Tb2.81Ce0.04Gd0.15Al5O12 phosphor generates warmer light than the WLEDs containing Y2.96Ce0.04Al5O12 and Tb2.96Ce0.04Al5O12 phosphors. Moreover, the WLEDs fabricated by integrating a blue LED chip and Ce3+/Gd3+-co-doped Tb3Al5O12 phosphors show outstanding colour stability when driven under different currents.

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