CaSb_2O_6∶Bi^(3+),Eu^(3+)荧光粉的制备和发光性质

Synthesis and Luminescence of CaSb_2O_6∶Bi^(3+), Eu^(3+)Phosphors

采用共沉淀法及1 200℃后续煅烧4 h,成功制备了CaSb_2O_6∶Bi^(3+),Eu^(3+)荧光粉,并对其结构及发光性能进行了研究。所制备荧光粉颗粒为六边形类圆饼状,平均尺寸在100~600 nm之间。对CaSb_2O_6∶Bi^(3+),Eu^(3+)发光的机理分析表明,Bi^(3+)对Eu^(3+)的发光存在高效的敏化与能量传递。当Bi^(3+)和Eu^(3+)的掺杂浓度分别为0.5%和8%,Eu^(3+)位于580 nm(5D0→7F0)处的荧光发射显著增强,Bi^(3+),Eu^(3+)共掺样品的荧光强度是Ca Sb2O6∶Eu^(3+)的10倍左右。调节Bi^(3+)/Eu^(3+)离子掺杂比,色坐标呈现了从蓝、白光到红光的变化,表明该荧光粉可分别作为蓝或红色荧光粉使用,甚至可实现从蓝、白光到红光的自由调控,这为白光LED荧光粉的发展提供了参考。

The novel phosphors, Bi^（3＋）and Eu^（3＋）co-doped CaSb_2O_6 were obtained by co-precipitation technique followed by heat-treatment at 1 200 ℃ for 4 h. Their properties were investigated in detail. The phosphor has an average size of around 100 ~600 nm with hexagon round pie-like shape. It was found that the luminescence of Eu^（3＋）ions in the CaSb_2O_6 could be efficiently sensitized by co-doping of Bi^（3＋）ions involving energy transfer from Bi^（3＋）to Eu^（3＋）. The ~5D_0→~7F_0transition emission of Eu^（3＋）was enhanced by a factor of ten when the Bi^（3＋）content was0.5% as compared to that of the sample without Bi^（3＋）doped. Typically, it was observed that the CIE chromaticity coodinates varying from blue to white-light and eventually to red light could be achieved by tuning the relative ratio of Bi^（3＋）/Eu^（3＋）in CaSb_2O_6∶Bi^（3＋）, Eu^（3＋）. Hence, these results indicate that CaSb_2O_6∶Bi^（3＋）, Eu^（3＋）phosphors can serve as a potential application material for phosphor-converted white-light UV-LEDs.