Systematic Tuning of Persistent Luminescence in a Quaternary Wurtzite Crystal Through Synergistic Defect Engineering

Persistent luminescence (PersL), characterized by continuous light emission after cessation of excitation, finds enormous applications in night displays, optoelectronics, and biomedicine. Despite the long history and a recent renaissance of PersL research, there still lacks a versatile approach for deliberate control over PersL in a single material system, which is crucial for mechanistic understanding and rational design of PersL. Herein, a strategy for the systematic tuning of PersL in the wavelength, time, and temperature domains in a wurtzite CaZnOS crystal, based on synergistic defect engineering (i.e., simultaneous control of activator/trap states and trap-filling process) through combinatorial doping in the double cationic sites, is presented. This design principle can be harnessed to produce PersL in a vast collection of emitters with distinct electronic transitions, including ns(2)-nsnp, 3d-3d, 4f-4f, and donor-acceptor recombination, which is inaccessible to the existing material systems. The results highlight that the strategy of synergistic defect engineering can provide unprecedented PersL properties with stimulus-responsive features for information encryption and photoexcitation-free optical thermometry. © 2023 Wiley-VCH GmbH.