Eu^(3+)、Gd^(3+)共掺杂Sr_2SiO_4荧光粉的液相沉淀合成及能量转移发光性能

Fabrication of Eu^(3+)and Gd^(3+) Codoped Sr_2Si O_4via Precipitation Method and Their Photoluminescence Properties through Energy Transfer

采用液相沉淀法合成了钆单掺杂、铕单掺杂、钆-铕共掺杂的硅酸锶发光材料。用X-射线衍射(XRD)对其结构表征。利用荧光光谱(PL)方法对合成的样品进行发光性能表征。研究结果表明:在250nm紫外光为激发波长时,Eu^(3+)单掺杂Sr_2SiO_4∶0.04Eu^(3+)的发光光谱出现Eu^(3+)的5D0→7F1(584nm)、5D0→7F2(614nm)、5D0→7F3(626nm)跃迁发光峰,钆-铕共掺杂Sr_2SiO_4∶x Gd3+,0.04Eu^(3+)发光体系中,主要表现为Eu^(3+)离子的特征发射。探讨了在硅酸锶发光体中Gd^(3+)→Eu^(3+)能量传递的机理,主要为电偶极-电偶极相互作用。当改变Eu^(3+)离子的掺杂浓度时,样品表现为Eu^(3+)离子的特征发射,此时材料发橙色光。保持Gd^(3+)、Eu^(3+)离子掺杂浓度不变,K+作为电荷补偿剂,对材料发光强度影响很小。

Gd^3＋ doped,Eu^3＋ doped and Gd^3＋ , Eu^3＋ co-doped Sr2SiO4 were prepared by precipitation method. The products were characterized by the X-ray diffraction（XRD）. The luminescence properties of the material were measured by excitation and emission spectra. The emission spectra of Sr2SiQ： 0.04Eu^3＋ showed three emission peaks located at 584nm,614nm,626nm（excited at 250nm）, which was attributed to the typical ^5D0→^7F1,^5D0→^7F2 ,^5D0→^7F3 transition of Eu^3＋. The material Sr2SiO4 ：xGd^3＋ ,yEu^3＋ had one luminescence center Eu^3＋. Energy transfer process and mechanism were analysised, the mechanism of energy transfer from Gd^3＋ to Eu^3＋ in Sr2SiO4 ： xGd^3＋ ,yEu^3＋ is resonant transfer,in which electric dipole-dipole interaction plays a leading role. When adding the concentration of Eu^3＋, red and yellow emissions were attributed to ^5D0→^7F1 （590nm） and ^5D0→^7F2 （609nm） of Eu^3＋. It was presented that the emission spectrum intensity of Sr2SiO4： 0.04Gd^3＋ ,0.04Eu^3＋ phosphor was not en- hanced by co-doped with K^＋ ion,and the relative luminescence intensity was not increased.