Efficient Trichromatic Ultralong Persistent Luminescence Activated by Body Temperature Toward Convenient Information Encryption and Storage

ABSTRACT Long‐persistent luminescence (LPL) materials, celebrated for their remarkable ability to capture and gradually release light over extended durations, have catalyzed advances in domains such as optical data storage and bioimaging. However, the synthesis of efficient, multicolor ultralong LPL with precise modulation of duration remains a formidable challenge. Here, we introduce an effective strategy for inducing trichromatic ultralong LPL in Cs 2 NaScCl 6 :Sb 3+ through meticulous defect engineering. By judiciously adjusting the dosage of hydrochloric acid during synthesis, we systematically regulate the formation of Na + and Cl − vacancies as well as Sb 3+ ‐induced lattice distortions, affording unprecedented control over the material's luminescent properties. This approach culminates in the achievement of a record‐breaking blue afterglow exceeding 30 h for naked eye, alongside green and red persisting for 48 and 24 h, respectively. Notably, the dual self‐trapped exciton (STE) emissions exhibit disparate thermal behaviors, with the higher‐energy STE demonstrating anti‐thermal quenching, while the lower‐energy counterpart undergoes typical thermal quenching. For the first time, we elucidate the activation of LPL via body temperature, enabling information retrieval through tactile interaction. This innovative material showcases profound potential for x‐ray imaging and secure data encoding, offering a novel avenue for the development of advanced LPL materials with finely tuned emission characteristics.