Tunable color of Tb3+/Eu3+/Tm3+-coactivated K3La(PO4)2 via energy transfer: A single-phase white-emitting phosphor. (July 2019)

• Record Type: Journal Article
• Authors: Wu, Xiulan; Bai, Wenni; Hai, Ou; Ren, Qiang; Zheng, Jinle; Ren, Yuhan
• Is Part Of: Optics & laser technology. Volume 115(2019)
• Page Start: 176
• Page End: 185
• Publication Date: 2019-07
• Subjects: K3La(PO4)2 -- Solid-state reaction -- White-light emitting phosphor -- Energy transfer; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2019.02.021
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: A new Tb 3+ /Eu 3+ /Tm 3+ co-doped K3 La(PO4 )2 phosphor was firstly synthesized. K3 La(PO4 )2 :Tb 3+, Eu 3+ is a green to orange-red color tunable phosphor. The highest energy transfer efficiency of 85.89% was obtained for the phosphor doped with 7 mol% Eu 3+ . The thermal activation energy (Δ E ) is obtained to be about 0.2 eV via the Arrhenius equation. Abstract: A series of Tm 3+, Tb 3+, Eu 3+ coped K3 La(PO4 )2 phosphors was synthesized via solid-state reaction. The compounds were characterized by X-ray diffraction (XRD), photoluminescence (PL) spectra as well as fluorescent decay curves. The energy transfers from Tb 3+ to Eu 3+ in the K3 La(PO4 )2 host were investigated according to the Inokuti–Hirayama theoretical model which suggests they are of the resonant type via a dipole–dipole mechanism. By adjusting the doping concentrations of Tb 3+, Tm 3+ and Eu 3+, a white emission can be reached in the K3 La(PO4 )2 host. The energy transfer efficiency and the CIE coordinates of K3 La(PO4 )2 :RE 3+ (RE = Tm, Tb, Eu) phosphors were calculated. In addition, the temperature-dependent emission showed good thermal stability of as-prepared phosphors. The obtained properties indicated that prepared compounds can be used as a single-component white emitting phosphor in WLEDs structures.