First-principles study on persistent luminescence mechanism of LiYGeO_(4):Eu^(3+)

作     者：Shihang Zhou Bibo Lou Chong-Geng Ma Min Yin Shihang Zhou;Bibo Lou;Chong-Geng Ma;Min Yin

作者机构：Xinjiang Key Laboratory for Luminescence Minerals and Optical Functional MaterialsSchool of Physics and Electronic EngineeringXinjiang Normal UniversityUrumqi830054China CAS Key Laboratory of Strongly-Coupled Quantum Matter Physicsand School of Physical SciencesUniversity of Science and Technology of ChinaHefei230026China School of Optoelectronic Engineering&CQUPT-BUL Innovation InstituteChongqing University of Posts and TelecommunicationsChongqing400065China 

出 版 物：《Journal of Rare Earths》 (稀土学报（英文版）)

年 卷 期：2023年第41卷第10期

页      面：1519-1524,I0002页

核心收录：

学科分类：081702[工学-化学工艺] 08[工学] 0817[工学-化学工程与技术] 

基　　金：the Natural Science Foundation of Xinjiang Uygur Autonomous Region(2022DO1A98) the National Natural Science Foundation of China(11974338,11974022,21805082) China-Poland Intergovernmental Science and Technology Cooperation Program(202015/10) 

主　　题：Persistent Iuminescence Eu^(3+) Charge transfer Point defects First-principles Rare earths 

摘      要：LiYGeO_(4):Eu^(3+)is a red persistent luminescent material with a duration of more than 21 *** its persistent luminescence phenomenon has been fully studied,its detailed mechanism is still the subject of ***,we performed first-principles study on the intrinsic point defects and the charge transfer processes in LiYGeO_(4):Eu^(3+)to reveal the mechanism of persistent *** results show that,under charge transfer excitation,the electron is promoted from the valence band(oxygen ion ligand)to the central Eu^(3+)ion to form Eu^(2+)ion in LiYGeO_(4):Eu^(3+),leaving a hole *** charge transfer excitation can relax quickly to the excited state of the Eu^(3+)ion,which produces the characteristic^(5)D_(0)→^(7)F_(J)(J=0-6)*** Li vacancies(V_(Li))and the antisite defects of Li replacing Y site(Li_(Y))and Y replacing Li site(YLi)are main defects,while O vacancies(V_(O))are less important in concentration due to high formation *** and Liy can serve as hole-type traps,with the trap depths suitable for trapping the holes produced by *** delayed release holes can combine with the Eu^(2+)left behind by the illumination,leading to persistent *** VLi trap is shallower than Li_(Y),and the latter is responsible for the long duration of persistent luminescence.A schematic based on the calculation results is constructed to illustrate the mechanism of persistent luminescence.