Photoluminescence properties of Tm3+/Tb3+/Sm3+tri-doped Na5Y9F32 single crystal with high thermal stability for white light-emitting diodes

• 作者: Yang Qiao Xiong Zhou Jianli Zhang Haiping Xia Hongwei Song Baojiu Chen
• 来源期刊: 稀土学报（英文版）
• 年，卷（期）: 2021,（5）
• 所属期刊栏目: SPECTROSCOPY, LUMINESCENCE AND PHOSPHORS
• 页码范围: 512-519
• 页数: 8页
• 语种: 英文

摘要

A novel Tm3+/Tb3+/Sm3+ tri-doped Na5Y9F32 single crystal was synthesized by a modified Bridgman method for the propose of white light emitting diodes. The fluorescence spectra of various Sm3+ ion concentrations and fixed 0.4 mol％ Tm3+and 0.5 mol％Tb3+were measured and studied systematically excited by near-ultraviolet light of 355 nm. The Sm3+ ion concentration takes apparent effect on the relative intensity of peaks in the visible region and the color coordinate combining from these emission bands. A near pure white light emission with color coordinates (0.3295, 0.3057) and color temperature (5657 K) can be obtained when the concentrations of Tm3+, Tb3+and Sm3+ions are 0.4 mol％, 0.5 mol％and 0.8 mol％, respectively. Furthermore, the practical down-conversion internal quantum yield was measured by integrating spheres at about 14.39％. The tri-doped Na5Y9F32 single crystal shows a high thermal stability inferring from the temperature dependent emission in which the integrated emission intensities are reduced only by ～3％ with the increase of temperature from 280 to 450 K. The present results demonstrate that the Tm3+/Tb3+/Sm3+tri-doped Na5Y9F32 single crystal may provide a promising candidate for white light-emitting diodes, luminescent materials and fluorescent display devices.