研究溶胶-凝胶法合成Sr2Al2SiO7:Ce^3+,Tb^3+白色长余辉发光材料。用X射线粉末衍射鉴定Sr2Al2SiO7晶型结构的形成。通过扫描电镜照片可以观察到合成粉体的微观结构,是由0.5-11μm烧结良好的规则颗粒组成。荧光分光光度测定了光谱特性。Ce^3+,Tb^3+共激活的Sr2Al2SiO7白色长余辉材料有4个发射光谱,其中包括:在414nm Ce^3+的特征光谱和在482,543和588nm Tb^3+的特征光谱。通过改变激活离子的组成可以观察到Tb^3+和Ce^3+之间的能量转移。溶胶-凝胶法合成的磷光体形成晶相更加完全,颗粒直径小、粉体松散,具有更强的发光起始强度和更优异的余辉性能。
Sr2Al2SiO7: Ce^3+,Tb^3+ white emitting phosphors were fabricated by the sol-gel method. X-ray powder diffraction (XRD) analysis confirmed the formation of Sr2Al2SiO7: Ce^3+,Tb^3+. Scanning electron microscopy (SEM) observation indicated that the microstructure of the phosphor consisted of regular fine grains with an average size of about 0.5-1μm. Luminescence properties were analyzed by measuring the photoluminescence spectra. The resultant (Ce^3+, Tb^3+)-codoped Sr2Al2SiO7 phosphors show four main emission peaks: one at 414 nm for Ce^3+ and three at 482, 543 and 588 nm for Tb^3+. The emission spectra of the samples with different doping concentrations show that the Tb^3+ emission is dominantly due to the persistent energy transfer from Ce^3+. The decay characteristic is better than that prepared by solid-state process in the comparable condition. The codoped phosphor showed long persistence white phosphorescence.