College of Physics Science & Technology, Hebei Key Lab of Optic-Electronic Information and Materials, Hebei University, Baoding 071002, China.
College of Physics Science & Technology, Hebei Key Lab of Optic-Electronic Information and Materials, Hebei University, Baoding 071002, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2019 Apr 15;213:141-149. doi: 10.1016/j.saa.2019.01.038. Epub 2019 Jan 16.
A series of CaBOCl:Ce, Tb, Sm are successfully synthesized by a high temperature solid state reaction. And the crystal structure, luminescence property and energy transfer mechanism of Ce/Sm, Tb/Sm and Ce/Tb/Sm in CaBOCl are investigated. There is an interesting phenomenon that the right side of the Ce emission spectra in CaBOCl:Ce, Sm compresses gradually with increasing the Sm concentration. By means of refinement, it can be found that Sm ions are mainly occupied in the Ca sites, because the cell of the Ca lattice is easily occupied. Then, the emission peak2 of Ce in Ca sites occurs to blue shift. While the emission peak1 of Ce in Ca sites is basically stability. However, the emission of Ce in CaBOCl:Ce, Tb, Sm have different changes with increasing the Sm concentration that the emission peaks of Ce shift to long wave at first then to short wave and the FWHM remains stability. This can be attributed to the existence of Tb. For the energy transfer mechanism, according to Dexter's energy transfer theory and Reisfeld's approximation, the energy transfer process of Ce/Sm and Tb/Sm should be the dipole-dipole interaction. And white emitting phosphor is achieved by the efficient energy transfer.
通过高温固相反应成功合成了一系列 CaBOCl:Ce、Tb、Sm。研究了 CaBOCl 中 Ce/Sm、Tb/Sm 和 Ce/Tb/Sm 的晶体结构、发光性能和能量传递机制。有趣的现象是，随着 Sm 浓度的增加，Ce 发射光谱在 CaBOCl:Ce、Sm 的右侧逐渐压缩。通过精修，可以发现 Sm 离子主要占据 Ca 位，因为 Ca 晶格的晶格容易被占据。然后，Ca 位的 Ce 发射峰 2 发生蓝移。而 Ca 位的 Ce 发射峰 1 基本稳定。然而，随着 Sm 浓度的增加，CaBOCl:Ce、Tb、Sm 中 Ce 的发射发生了不同的变化，Ce 的发射峰先向长波移动，然后再向短波移动，FWHM 保持稳定。这可以归因于 Tb 的存在。对于能量传递机制，根据 Dexter 的能量传递理论和 Reisfeld 的近似，Ce/Sm 和 Tb/Sm 的能量传递过程应该是偶极-偶极相互作用。通过有效的能量转移实现了白色发射磷光体。
