Mechanism of the trivalent lanthanides' persistent luminescence in wide bandgap materials

Leipeng Li; Tianyi Li; Yue Hu; Chongyang Cai; Yunqian Li; Xuefeng Zhang; Baolai Liang; Yanmin Yang; Jianrong Qiu

doi:10.1038/s41377-022-00736-5

Mechanism of the trivalent lanthanides' persistent luminescence in wide bandgap materials

Light Sci Appl. 2022 Mar 8;11(1):51. doi: 10.1038/s41377-022-00736-5.

Authors

Leipeng Li^#¹, Tianyi Li^#¹, Yue Hu^#¹, Chongyang Cai^#¹, Yunqian Li¹, Xuefeng Zhang¹, Baolai Liang^{1

2}, Yanmin Yang³, Jianrong Qiu⁴

Affiliations

¹ Hebei Key Laboratory of Optic-electronic Information and Materials, College of Physics Science & Technology, Hebei University, Baoding, 071002, China.
² California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA.
³ Hebei Key Laboratory of Optic-electronic Information and Materials, College of Physics Science & Technology, Hebei University, Baoding, 071002, China. yangym@hbu.edu.cn.
⁴ State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310058, China. qjr@zju.edu.cn.

^# Contributed equally.

Abstract

The trivalent lanthanides have been broadly utilized as emitting centers in persistent luminescence (PersL) materials due to their wide emitting spectral range, which thus attract considerable attention over decades. However, the origin of the trivalent lanthanides' PersL is still an open question, hindering the development of excellent PersL phosphors and their broad applications. Here, the PersL of 12 kinds of the trivalent lanthanides with the exception of La³⁺, Lu³⁺, and Pm³⁺ is reported, and a mechanism of the PersL of the trivalent lanthanides in wide bandgap hosts is proposed. According to the mechanism, the excitons in wide bandgap materials transfer their recombination energy to the trivalent lanthanides that bind the excitons, followed by the generation of PersL. During the PersL process, the trivalent lanthanides as isoelectronic traps bind excitons, and the binding ability is not only related to the inherent arrangement of the 4f electrons of the trivalent lanthanides, but also to the extrinsic ligand field including anion coordination and cation substitution. Our work is believed to be a guidance for designing high-performance PersL phosphors.