ZnGa_2O_4:Cr^(3+)近红外长余辉荧光粉制备与光学性能研究

Preparation and Optical Properties of Near Infrared Persistent Luminescence Material of ZnGa_2O_4:Cr^(3+)

采用高温固相法制备了ZnGa_2O_4:Cr^(3+)近红外(660-1300 nm)长余辉荧光粉,并系统地研究了样品的荧光、长余辉、光激励发光及热释光性能.样品的余辉激发谱测试结果显示,ZnGa_2O_4:Cr^(3+)长余辉材料的余辉主要源自O^(2-)-Ga^(3+)之间的电荷迁移跃迁激发,而非Cr^(3+)离子的本征跃迁激发.光激励发光性能的研究表明,ZnGa_2O_4:Cr^(3+)在紫外光激发的余辉完全衰减后可以被近红外光再次激发出明亮的余辉,这说明ZnGa_2O_4:Cr^(3+)在紫外光信息写入后可以用红外光进行信息读出.根据实验测试结果采用导带电子复合发光模型对样品的发光机理进行了详细的阐述.

In this paper, the near infrared persistent luminescent material ZnGa2O4 ：Cr^3＋ is prepared by a high temperature solid state method and the photoluminescence, long persistent photoluminescence, photostimulated luminescence and thermoluminescence properties of ZnGa2O4 ： Cr^3＋ are studied in details. The persistent luminescence excitation spectra reveal that the persistent luminescence of ZnGa2O4 ：Cr^3＋ comes from the charge transfer transition from O^2- to Ga^3＋ instead of the intrinsic transition of Cr^3＋. The investigation in photo-stimulated persistent luminescence indicates that the sample can emit bright persistent luminescence again under infrared light excitation after the UV light excited persistent luminescence decays completely. The result shows that the UV light written information in ZnGa2O4 ：Cr^3＋ can be read by infrared light. Moreover, in accordance with the result, the recombination luminescence model of conduction electrons is employed to elaborate the luminescence mechanism of the sample.