文献类型：期刊文献

英文题名：Luminescence spectra and energy transfer of Tm³⁺ and Tb³⁺ doped in LiMgPO₄ phosphors

作者：Xu Zhuo[1];Guo Jing-Yuan[1,2];Xiong Zheng-Ye[1,3];Tang Qiang[2];Gao Mu[1]

机构：[1]Guangdong Ocean Univ, Sch Elect & Informat Engn, Zhanjiang 524088, Peoples R China;[2]Sun Yat Sen Univ, Sch Phys, Guangzhou 510275, Peoples R China;[3]Zhanjiang Univ Sci & Technol, Inst Intelligent Mfg, Zhanjiang 524094, Peoples R China

年份：2021

卷号：70

期号：16

外文期刊名：ACTA PHYSICA SINICA

收录：SCI-EXPANDED(收录号：WOS:000690386300032)、、WOS

基金：Project supported by Science and Technology Planning Project of Guangdong Province, China (Grant No. 2015A020216020), the National Natural Science Foundation of China (Grant No. 11375278) and Guangdong Ocean University, China(Grant No. CXXL2019260).

语种：英文

外文关键词：LiMgPO4; thermoluminescence; luminescence; energy transfer

外文摘要：LiMgPO4 (LMP) phosphor doped with rare earth is a promising radiation dosimeter material. Thermoluminescence (TL) spectroscopy is an effective method to study the carrier traps and luminescence centers in materials. To study the luminescent mechanism of rare-earth-doped LMP phosphors, LMP phosphors doped with Tm and Tb (LMP:Tm, LMP:Tb and LMP:Tm, Tb) are prepared by high temperature solid state reaction. The TL glow curve and TL spectrum of the phosphors are measured by the linear heating method, and compared with the photoluminescence (PL) spectrum. The shape of the TL glow curve of LMP phosphor varies with the doping active impurities, but the TL glow curves can be fitted by seven TL peaks. Double-doping Tm3+ and Tb3+ in LMP phosphor can enhance the TL intensity of the fifth peak (E similar to 1.39 eV) and weaken the seventh TL peak (E similar to 1.70 eV). By comparing the PL spectra with TL spectra of the phosphors, it can be seen that the TL spectra are more complex than the PL spectra excited by ultraviolet light (lambda = 352 nm). In the TL process, the electrons which are excited to the conduction band release the energy to recombination centers, and the released energy can more effectively excite the rare earth ions from the ground state to excited states, resulting in the more TL emitting peaks than in the the PL process. Although Tm3+ and Tb3+ can be the luminescent centers in LMP phosphors when Tm3+ and Tb3+ are doped in LMP simultaneously, Tb3+ ions are likely to act as sensitizers in LMP:Tm and LMP:Tb phosphor, and Tb3+ ions transfer energy to the low-energy Tm3+ ions, which makes the luminescent centers, Tm3+ ions, excited to the high-energy state and then de-excited with emitting light. This result is also proved by the fact that the luminescence decay of Tb3+ in phosphors increases with Tm3+ concentration increasing. The energy transfer through non-radiative transition is more significant at higher temperature.