LaOBr:Eu^(3+)的制备及发光特性

Preparation and luminescence properties of LaOBr:Eu^(3+)

采用固相合成法制备了Eu3+掺杂的LaOBr发光材料,研究了不同物质的量分数的Eu3+对发光性质的影响,其中Eu3+的物质的量分数为0.1%,0.2%,0.5%,1%.X线衍射图表明:所得样品为纯相的LaOBr.测量了不同物质的量分数的激发谱、发射谱及荧光寿命.通过对Eu3+衰减曲线的拟合,得到在相同Eu3+的物质的量分数下,从电荷迁移带跃迁到5 D0能级时间比5 D2能级跃迁到5 D0能级时间短,但从5 D0能级跃迁到基态能级的时间基本相同,说明Eu3+之间存在交叉弛豫现象.利用Judd-Oflet理论,从发射光谱获得了Eu3+的光学跃迁强度参数Ωλ(λ=2,4).

The Eu3＋ doped LaOBr phosphor was synthesized by solid state reaction method and the properties with different concentrations of Eu3＋ was investigated, which the concentration of Eu3＋ was 0. 1%, 0.2 %, 0.5 %, 1%. The X-ray diffraction data showed that the samples were pure LaOBr. The ex- citation spectrum, the emission spectrum and the fluorescence lifetime were obtained by fluorescence spec- trometer. It could be easily obtained that the time of charge transfer band transition to 5D0 was shorter than 5D2 to 5D0 from the fitting data, but it was almost equal to the time from 5D0 to ground state. It illus- trated that there were cross relaxation between Eu3＋ ions. The Ω2 and Ω4 parameters of Eu3＋ for optical transition were calculated by Judd-Oflet theory.