Spectral Decoupling Between Radioluminescence and Persistent Luminescence in Bi3+-Doped LiLu(WO4)2 for High-Security Information Encryption

Abstract

X-ray-stimulated persistent luminescence (PersL) materials hold significant promise for high-security anti-counterfeiting, information storage. However, the absence of spectral difference between radioluminescence (RL) and PersL in current materials severely restricts their application in multilevel optical encryption. In this work, we report a novel LiLu(WO4)2:Bi3+ phosphor that exhibits blue RL under X-ray irradiation and yellow PersL with a duration exceeding 8 h after X-ray cessation. Finally, “optical safe” based on LiLu(WO4)2:Bi3+ and LiLu(WO4)2 with attractive performance is designed for advaced information encryption with high security.