Hydrothermal assisted synthesis and photoluminescence of (Y1-xEux)(2)WO6 red phosphors
Shi, X; Li, JiG; Zhu, Qi; Li, X; Sun, X
| HERO ID | 4132584 |
|---|---|
| In Press | No |
| Year | 2017 |
| Title | Hydrothermal assisted synthesis and photoluminescence of (Y1-xEux)(2)WO6 red phosphors |
| Authors | Shi, X; Li, JiG; Zhu, Qi; Li, X; Sun, X |
| Journal | Journal of Alloys and Compounds |
| Volume | 695 |
| Page Numbers | 1984-1992 |
| Abstract | Phase-pure (Y1-xEux)(2)WO6 (x = 0.2-0.11) red phosphors (average crystallite size similar to 66 nm) in a monoclinic structure have been calcined at 1300 degrees C from their precursors autoclaved from the mixed solutions of rare-earth nitrate and sodium tungstate dihydrate (Na2WO4.2H(2)O) at 180 degrees C and pH similar to 10, instead of the commonly adopted pH values of 3-7, without the use of any surfactant. The materials were characterized in detail by the combined techniques of XRD, FT-IR, FE-SEM, TEM, EDS, and optical spectroscopy to reveal (1) the phase structure, morphology, and spatial cation distribution of the hydrothermal product, (2) the course of phase and morphology evolution that leads to the targeted tungstate phosphor, and (3) the effects of Eu3+ content on photoluminescence properties, including excitation/emission, asymmetry factor of luminescence (D-5(0) -> F-7(2)/D-5(0) -> F-7(1) intensity ratio), fluorescence lifetime, and CIE chromaticity coordinates. Through energy transfer from the [WO6](6-) ligands to Eu3+, the (Y1-xEux)(2)WO6 phosphors exhibit sharp (D0 -> FJ)-D-5-F-7 (J = 0-4) emissions upon UV excitation into the O2--W6+ charge transfer band peaked at 327 nm, with the red emission at 611 nm being the most prominent (D-5(0)-> F-7(2) transition of Eu3+). The optimal Eu3+ content was determined to be similar to 9 at.% (x = 0.09), and concentration quenching of luminescence was analyzed to be owing to exchange interaction. The emission color moves closer to the red region in the CIE chromaticity diagram with increasing Eu3+ doping, while fluorescence lifetime of the 611 nm emission, analyzed to be around 1.05 +/- 0.05 ms, shows weak dependence on the Eu3+ content. (C) 2016 Elsevier B.V. All rights reserved. |
| Doi | 10.1016/j.jallcom.2016.11.033 |
| Wosid | WOS:000391817600248 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Keyword | Tungstate; Hydrothermal; Calcination; Phase evolution; Red phosphors; Photoluminescence |