Long afterglow phosphors SrLaGa3O7:xSm3+were prepared by solid state reaction. The crys-tal structure and luminescent properties of the samples were studied via XRD, photoluminescent (PL) and thermoluminescent (ThL) spectra. Furthermore,the effect of doping Sm3+on long afterglow proper-ties of SrLaGa3O7:xSm3+was detailedly investigated. The obtained results show that SrLaGa3O7exhibites long afterglow emission located at 386 nm after the excitation of 254 nm UV light,which can persist more than 60 min. The existence of vacancies in SrLaGa3O7is responsible for the long afterglow emission. Fol-lowing the increase of doping Sm3+content,the luminescent and afterglow intensity increases and arrives at the strongest values and then decreases. In addition, the luminescent and afterglow emission wave-length shifts towards longer wavelength. When the doping Sm3+mole fraction reaches 0.5%,SrLaGa3O7 possesses the best long afterglow properties. The thermoluminescence spectra results indicate that the do-ping Sm3+can result in two different traps,which are created by V¨O and V″Sr vacancies. These traps affect not only the PL intensities but also the afterglow properties.%采用高温固相法制备了SrLaGa3O7:xSm3+长余辉材料,通过XRD、荧光光谱、热释光谱分别对样品的结构以及发光性能进行了研究,探究了Sm3+掺杂浓度对样品自身长余辉发光性能的影响.研究结果表明:样品在254 nm紫外光照射后,SrLaGa3O7:xSm3+在386 nm有明显的长余辉发光,可持续60 min,主要是由于样品中空位引起的发光.随着掺杂Sm3+浓度的增加,样品的发射光谱和余辉强度先增强后减弱,并出现明显的红移现象,这与Sm3+掺杂所造成的空位浓度密切相关.当Sm3+的摩尔分数达到0.5%时,样品在420 nm处展现最佳的长余辉性质.热释光谱表明掺杂后的样品中存在两种不同的陷阱,分别是由氧空位和锶空位引起的,这两种陷阱不仅影响样品的发光强度,而且充当俘获中心从而影响样品的余辉性能.
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