Preparation and characterization of a green emitting Li₂Ca_0.4Sr_0.6SiO₄:Tb³⁺ phosphor with afterglow behavior

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• 作者：Xinyu Li ; Dongyun Zhang ; ^{dyz@sit.edu.cn} ; Yue Chen ; Chengkang Chang
• 关键词：A. Powders ; solid state reaction ; C. Optical properties ; Long afterglow ; Traps
• 刊名：Ceramics International
• 出版年：2017
• 出版时间：1 February 2017
• 年：2017
• 卷：43
• 期：2
• 页码：1677-1681
• 全文大小：783 K
• 卷排序：43

文摘

A novel green emitting long afterglow phosphor Li2Ca0.4Sr0.6SiO4:Tb3+ was obtained via a high temperature solid-state reaction in air atmosphere. X-ray diffraction (XRD), photoluminescence spectroscope (PLS), long afterglow spectroscope (LAS) and thermal luminescence spectroscope (TLS) were performed to characterize the physical properties of the phosphors. Typical 5D4-7Fj transitions of Tb3+ ions were detected by PL spectra, corresponding to CIE chromaticity coordinates of x =0.3456, y =0.5745. An optimal concentration of Tb3+ in the substrate was determined as 0.8 at%. The Li2Ca0.4Sr0.6SiO4 phosphors showed a typical afterglow behavior when the UV source was switched off. A typical triple exponential decay behavior was confirmed after fitting the experimental data. Thermal simulated luminescence study further indicated that the afterglow behavior of Li2Ca0.4Sr0.6SiO4:Tb3+ phosphors was generated by the recombination of electrons with the holes resulted from the doping of rare-earth ions (Tb3+) in Li2Ca0.4Sr0.6SiO4 host. The long afterglow luminescence mechanism of Li2Ca0.4Sr0.6SiO4:Tb3+ is illustrated and discussed in detail on the basis of experimental results.