Substitution priority of Eu2+in multi-cation compound Sr0.8Ca0.2Al2Si2O8 and energy transfer

• 来源期刊: 中国物理B（英文版）
• 关键词: luminescence phosphors energy transfer substitution priority
• 年，卷（期）: 2018,（1）
• 页码范围: 575-583
• 页数: 9页
• 语种: 英文
• DOI: 10.1088/1674-1056/27/1/017802

摘要

A blue phosphor was obtained by doping Eu2+ into a multi-cation host Sr0.8Ca0.2Al2Si2O8 through high tempera-ture solid state reaction. The emission spectra show a continuous red-shift behavior from 413 nm to 435 nm with Eu2+concentration increasing. The substitution priority of Eu2+ in Sr0.8Ca0.2Al2Si2O8 was investigated via x-ray diffraction (XRD) and temperature properties in detail:the Ca2+ions are preferentially substituted by Eu2+at lower doping, and with the Eu2+concentration increasing, the probability of substitution for Sr2+is greater than that of replacing Ca2+. Accord-ingly, we propose the underlying method of thermal property to determine the substitution of Eu2+ in the multi-cation hosts. Moreover, the abnormal increase of emission intensity with increasing temperature was studied by the thermolumi-nescence spectra. The energy transfer mechanism between the Eu2+ions occupying different cation sites was studied by the lifetime decay curves. A series of warm white light emitting diodes were successfully fabricated using the blue phos-phors Sr0.8Ca0.2Al2Si2O8:Eu2+with commercial red phosphor (Ca Sr)SiAlN3:Eu2+and green phosphor (Y Lu)3Al5O12:Ce3+, and the luminescent efficiency can reach 45 lm/W.