长余辉发光粉Ba1-xCaxAl2O4:Eu2+, RE3+的发光特性及光谱分析

采用高温固相法制备了长余辉发光粉Ba1-xCaxAl2O4:Eu^2 ,RE^3 (RE^3 =Dy^3 ,Nd^3 )，测量了其发射光谱、激发光谱、余辉衰减光谱和热释光谱，分析了其发光特性。在紫外线的激发下样品的发射波长随着x的变化而变化，x从0到0．6的范围变化时，发射波长相应地从498nm减小到440nm，当x大于0．6以后，波长保持440nm不再变化。通过XRD光谱对其结构进行了分析，得出Ca离子在BaAl2O4基质中有极限溶解度x0=0．4，当x大于0．4时，基质结构中出现杂相。通过热释光谱，对基质中的陷阱情况进行了分析，解释了由于x值的不同而造成的余辉时间长短的差异。

Luminescence Properties and Spectral Analysis of Long Phosphorescent Phosphors: Ba1-xCaxAl2O4: Eu2+, RE3+

New long phosphorescent phosphors Ba_(1-x)Ca_xAl_2O_4: Eu~(2+), RE~(3+)(RE~(3+)=Dy~(3+), Nd~(3+)) with tunable color emission have been prepared by solid state reaction. The luminescence properties of the samples are discussed and analyzed. The emission spectra show that the tuning range of the color emission of the phosphors is between 498 and 440 nm, which is determined by x, under the excitation of UV. The wavelength of afterglow increases with increasing x until x equals 0.6, and when x equals 0.6, the (luminescence) property of Ba_(1-x)Ca_xAl_2O_4: Eu~(2+), RE~(3+)(RE~(3+)=Dy~(3+), Nd~(3+)) is similar to that of CaAl_2O_4: Eu~(2+), RE~(3+). The XRD measurements were performed to investigate the single phase states of the samples, and it was found that the single phase limit in the phosphors is below an x value of 0.4. The thermoluminescence curves imply that the traps in the hosts are different with different x value, which well explains the varying delay time of the samples.