燃烧法快速合成铝酸锶基质长余辉发光材料

SYNTHESIS OF SrAl_2O_4: Eu^(2+), Dy^(3+) PHOSPHORS WITH LONG-AFTERGLOW BY RAPID COMBUSTION

以燃烧法快速合成了Eu^(2+)，Dy^(3+)掺杂的铝酸锶发光粉，发光粉经自然光激发可观察到明亮的黄绿光，余辉可达12 h以上。用X射线粉末衍射、扫描电镜、透射电镜等分析了合成物的物相组成、显微结构与粒度等。结果表明：合成的发光粉主晶相是SrAl_2O_4，扫描电镜下呈卷曲片状，透射电镜下的一次粒子呈不规则粒状，粒子直径大多分布在60～100 nm以内。通过对荧光分光光度计所测定的合成样品的激发光谱、发射光谱和衰减曲线等光谱分析发现：合成物的发光是Eu^(2+)的4f^65d^1→4f^7的电子跃迁，而发光体的长余辉特性是由于发光体中Dy^(3+)的空位陷阱作用。

Eu2+, Dy3+ co-doped strontium aluminate phosphor powders with high brightness and long afterglow were prepared by combustion synthesis for several minutes. After excitement the bright yellow green light was observed and its afterglow lasted more than 12 h. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscope (TEM). The results of XRD show that the main crystalline phase is SrAl2O4. According to the observation of SEM, the particles of the sample is curl slice. The average size of particles ranges from 60 to 100 nm with irregular shape as indicated by TEM. The results of the spectroscopic analysis for the excitation spectrum, emission spectrum and decay curve characterized by fluorospectrophotometer indicate that the broad-band luminescence is due to the transitions from 4f6 5d1 to 4f7configuration of the Eu2+ ion, and the long afterglow is due to the effect of the vacancy trap of Dy3+.