摘要
首次介绍了一种新型长余辉材料 :Eu2 + ,Dy3 + 共掺杂硼铝锶长余辉玻璃陶瓷 ,该玻璃陶瓷用紫外灯、日光、荧光灯均可激发 ,发射黄绿色余辉 ,余辉的发射峰位于 5 16nm ,来自于Eu2 + 的 5d→ 8S7/ 2 跃迁。用12 0 0 0lx的荧光灯激发样品 2 0分钟 ,停止激发后 10秒时 ,该玻璃陶瓷的余辉亮度为 3 5 3cd/m2 ,色坐标为 :x =0 2 84 2 ,y =0 5 772 ;停止激发后 5小时 5 5分钟 ,该玻璃陶瓷的余辉亮度为 0 0 1cd/m2 ;停止激发 30小时后 ,余辉在黑暗中仍肉眼可见。文中对该玻璃陶瓷的相关性质进行了表征 。
Because glasses have particular properties, for example it is easy to be fabricated into products with various shape in the range from bulk plate to fine fiber, and many key optoelectronic components, e.g., amplifier, display and storage devices etc. are made of glass with special optical properties, therefore we think the studies on long lasting phosphorescent (LLP) glasses and glass ceramics are important in views of not only the traditional application of LLP materials, but researching of new optoelectronic materials and devices. This article introduces the study on a new kind of LLP material: Eu 2+ ,Dy 3+ co doped strontium aluminoborate glass ceramic with a composition of 29% B 2O 3,28% Al 2O 3,43% SrCO 3,0 1% Eu 2O 3 and 0 1% Dy 2O 3(mol%).Transparent Eu 2+ ,Dy 3+ co doped strontium aluminoborate glass with the same composition was synthesized under a CO atmosphere at 1550℃ which didn't emit LLP, however, opaque glass ceramic with LLP phenomenon was formed by appropriate heat treatment to glass. The XRD and infrared analysis show that the main microcrystalline phase in the sample is SrAl 2O 4.The excitation spectrum of the sample shows a broad band peaking at about 366nm which is due to the f→d transition of divalent europium; the emission spectrum is alike with the long lasting phosphrescent spectrum, showing a band which peaks at 516nm attributed to 5d→ 8S 7/2 transition of divalent europium. Thus the LLP of the sample is due to the characteristic emission of Eu 2+ ion. The thermoluminescence spectrum consists of three Gaussian fitted components, which may indicate there exist three kinds of traps. When the glass ceramic is irradiated with fluorescent lamp with a power density of 1 2×10 4 lx for 20 minutes, the luminance of the sample is 3 53 cd/m 2 10 seconds after stopping the irradiation, the chromaticity coordinates are x=0 2842,y =0 5772. After 5 hours of the irradiation, the sample still has a luminance of 0 01cd/m 2 . The phosphorescence can be seen in dark even 30 hours after the irradiation. The decay of the luminescence is a complex process that consists of three parts: a fast decay, a intermidate and a long decay process. We considered that the formation of SrAl 2O 4 micro crystal was essential for the LLP of glass ceramic , it was very possible that Eu 2+ and Dy 3+ ions were incorporated in the SrAl 2O 4 micro crystal, thus the LLP of glass ceramic was emitted by Eu 2+ , Dy 3+ co doped SrAl 2O 4 micro crystal. However, directly proof showing the formation of SrAl 2O 4: Eu 2+ , Dy 3+ was absent. We suggest the LLP is due to the recombination of trapped holes and electrons which can be thermally released from trapping centers at room temperature. However, further studied should be carried on the mechanism of the LLP of Eu 2+ , Dy 3+ co doped strontium aluminoborate glass ceramic , as well as the relationship between the treatment processing of glass ceramic and its phosphorescent properties.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2002年第3期233-237,共5页
Chinese Journal of Luminescence
基金
国家重点基础研究基金资助项目 (G19980 613 12 )
