绿色荧光粉Ca_9Al(PO_4)_7:Tb^(3+),Ce^(3+)的发光特性

Luminescent Properties of Green Emitting Phosphor Ca_9Al(PO_4)_7:Tb^(3+), Ce^(3+)

采用固相法合成Ca9Al(PO4)7:Tb3+,Ce3+绿色荧光粉,研究了材料的发光性质。结果表明,以377 nm近紫外光作为激发源时,Ca9Al(PO4)7:Tb3+呈现出多峰特征,主峰位于491、545、589和623 nm,分别对应Tb3+的5D4→7F6,5D4→7F5,5D4→7F4和5D4→7F3跃迁发射,其中545 nm发射峰最强,从而材料整体发射绿光;监测545 nm发射峰,对应的激发光谱为多峰特征,覆盖300~390 nm;增大Tb3+的掺杂量,发现Ca9Al(PO4)7:Tb3+的发射强度逐渐增大,在实验范围内,并未出现浓度猝灭现象;通过添加A+(A=Li、Na和K)以及敏化剂Ce3+,有效增强了Tb3+在Ca9Al(PO4)7中的发射强度。测量了不同Tb3+掺杂量下材料的色坐标,发现Ca9Al(PO4)7:Tb3+的色坐标基本不变,位于绿色区域。

A green emitting phosphor of Ca9AI（PO4）7：Tb3＋, Ce3＋ was synthesized by a high-temperature solid-state method, and its luminescent properties were investigated. Under 377 radiation excitation, the emission spectrum of Ca9AI（PO4）7：Tb3＋ presents several peaks located at 491,545, 589 and 623 nm, which are ascribed to 5Dg→TF6, SD4→TFs, 5D4→TF4 and 5D4→TF3 transitions of Tb3＋, respectively. The most intensive emission of CagAI（PO4）7：Tb3＋ occurs at 545 rim, therefore showing green light. For the emission at 545 nm, the corresponding excitation spectrum extends from 300 nm to 390 nm, exhibiting the several excitation peaks. The emission intensities of Ca9AI（PO4）7：Tb3＋ are affected by Tb3＋ concentration. However, there is no concentration quenching effect. The emission intensities of CagAI（PO4）7：Tb3＋ can be enhanced by co-doped A＋ （A=Li, Na and K） and sensitizer Ce3＋. The CIE color coordinates of CagAI（PO4）7：xTb3＋ locate in the green region, which are not affected by Tb3＋ concentration.