Ce^3＋在Ba2ZnB2O6中的晶体学格位及其发光性能研究

Crystallographic Sites and Luminescence Properties of Ce^(3+) in Ba_2ZnB_2O_6

通过高温固相法合成了Ba_2ZnB_2O_6∶Ce^(3+)蓝色荧光粉。通过XRD、Rietveld结构精修、激发和发射光谱、荧光衰减曲线以及变温荧光光谱等,对荧光粉的晶体结构和发光性能进行了研究。结果表明:Ce^(3+)的掺入并未对基质的晶格结构产生影响,在350 nm近紫外光激发下,Ba_2ZnB_2O_6∶x Ce^(3+)的发射峰为位于430 nm的不对称的宽谱,最佳掺杂浓度为x=0.01,Ce^(3+)在Ba_2ZnB_2O_6晶格中占据Ba1和Ba3两种格位,随掺杂浓度升高更倾向于占据Ba3位。Ce^(3+)的择优占位使荧光粉的发光由蓝光向蓝绿色区域发生了明显的漂移。

A series of Ba2ZnB2O6∶ Ce^3＋blue-emitting phosphors were synthesized by high temperature solid-state reaction. The structure and photoluminescence properties of Ba2ZnB2O6∶ Ce^3＋were investigated by XRD patterns,PLE and PL spectra as well as temperature-dependent PL spectra and decay curves. Ba2ZnB2O6∶ Ce^3＋reveals a broad and asymmetric blue-emission band peaking at 430 nm under 350 nm excitation. The Rietveld refinement indicates the asymmetric emission band corresponding to the Ce^3＋in Ba1 and Ba3 sites. With Ce^3＋concentration increasing, the emission intensity of Ba2ZnB2O6∶ x Ce^3＋reaches the maximum at x = 0. 01 and Ce^3＋prefer to occupy the Ba3 site. The preferred occupation of Ce^3＋in Ba2ZnB2O6makes the color of phosphor tuning from blue to blue-green.