铝酸锶长余辉发光材料的光谱特性及陷阱浓度分析

Spectral properties and trap concentration analysis of strontium aluminate long afterglow phosphors

采用高温固相法制备了Sr0.96Al2O4:Eu0.02,Dy0.02,B0.08长余辉发光材料。利用XRD衍射仪、荧光分光光度计和热释光计量仪对样品进行了测试。对余辉衰减曲线的拟合表明,余辉曲线中的快衰减过程与V˙O˙陷阱有关,而慢衰减过程源于Eu˙Sr和Dy˙Sr陷阱中的电子释放;随着球磨时间的增加,Dy˙Sr陷阱浓度也随之增加。热释光光谱的曲线拟合表明,热释光峰反映的是Dy˙Sr陷阱的特性;当陷阱浓度相差不大时,动力学级次越小,陷阱中电子的局域性越强,基质导带底产生一个由局域态组成的带尾,陷阱深度随之减小。

The long afterglow luminescent materials Sro.96 A12 04 ： Euo.o2, Dyo.o2, Bo.08 were synthesized by solid-state reaction method. The materials were characterized by means of X-ray diffraction, fluorescence spectrophotometer and thermal luminescent spectroscope. Simulated results for the afterglow curves exhibit that the exponentially rapid decay component is attributed to the release of the electrons from Vo＇＂ , and the slow component is attributed to Eusr and Dyer. With the increasing of milling time, the Dysr concentration increases. The thermal luminescent spectra （TLS） from the curve fitting technique indicate that the TLS peaks are considered generating from Dyer. When the differences of the trap concentration of the samples are less, the lower the kinetic order is, the more remarkable the localized property of the trapped electron is, which results in the formation of localized state under the conduction band. Subsequently the trap depth decreases.