ABSTRACT The integration of photochromism (PC), time‐dependent phosphorescence color (TDPC), and persistent luminescence (PersL) into a singular inorganic material is highly desirable for advanced applications such as information encryption and UV monitoring. However, achieving such synergistic multimodal optical responses remains an outstanding challenge. Herein, a new optical material based on barium magnesium silicate (BMS) was constructed by co‐doping Eu and Fe/Co ions. This inorganic material system exhibits, for the first time, simultaneous reversible PC, TDPC, and PersL. Precise control of oxygen vacancies and trap distribution endows the materials with high color contrast, rapid response, and excellent reversibility. After 365 nm irradiation, tunable room‐temperature phosphorescence (RTP) with evolving emission colors is observed, while green PersL emerges after 254 nm excitation. Mechanistic investigations reveal that these multimodal responses arise from synergistic electron capture and recombination processes between defect centers and Eu ions. The practical application of this material has been demonstrated through the development of printable inks suitable for flexible UV sensors, dynamic information encryption, and multi‐level anti‐counterfeiting. This study proposes a feasible approach for designing high‐performance inorganic photo‐responsive materials, bridging the gap in TDPC research for inorganic systems and paving the way for their use in intelligent optical security and sensing.
Guo et al. (Sun,) studied this question.