Wide-Temperature Persistent Luminescence

Abstract

Traditional persistent luminescence (PersL) materials depend on the distribution of inherent traps within their structure, which are usually narrow and discontinuous, thereby restricting their functionality to a limited temperature range. The development of materials capable of PersL over a wide temperature range, represents a significant hurdle in the advancement of PersL technology. Here, this study deviates from the conventional method of relying on inherent traps and instead harness recoverable Frenkel defects within fluoride materials to broaden the operational temperature range for PersL. Under X-ray irradiation, Frenkel defects involving the migration of fluorine ions can be generated and recovered in real time, accompanied by the formation and dissipation of localized excitons, ultimately transferring energy to the luminescent centers. Notably, this recovery process is operative at all temperatures and is sufficiently slow-paced, ensuring that PersL can be observed across every temperature range (77–500K). Building on this mechanism, the production of multicolor wide-temperature PersL is readily attainable through the straightforward substitution of various luminescent centers. Significantly, X-ray-induced recoverable Frenkel defects have the potential to confer the characteristics of wide-temperature PersL to materials that inherently lack these attributes. This, in turn, provides a new design strategy for developing wide-temperature PersL materials.