Highly Stable Oxynitride Persistent Phosphors with Widely Distributed Traps for Information Storage and Anticounterfeiting

Abstract Persistent phosphors are widely investigated in indications, bio‐imaging, information storage, and anticounterfeiting. However, it remains a challenge to develop highly stable persistent phosphors with abundant and widely distributed traps. Here, a Ba_0.58Sr_0.4Al₃Si₃O₄N₅:0.02Yb²⁺ (Ba_0.6Sr_0.4Al₃Si₃O₄N₅:Yb²⁺) persistent phosphor with an excellent persistent luminescence (PersL) time of 383 min is reported before decaying to 0.32 mcd m⁻² due to the existence of abundant intrinsic electron traps. Ba_0.6Sr_0.4Al₃Si₃O₄N₅:Yb²⁺ owns a trap distribution ranging from 0.41 to 1.04 eV and has a remarkably broad full width at half maximum (FWHM) of TL curve (169 K) among currently reported persistent phosphors. The robust stability of Ba_0.6Sr_0.4Al₃Si₃O₄N₅:Yb²⁺ is evidenced by immersing in hot water and annealing at the high temperature for different time, which showed PersL retention rates of over 90%. Temperature‐assisted information storage in this persistent phosphor is successfully demonstrated. Furthermore, a step‐by‐step write‐in method is implemented in anticounterfeiting, and the coded information can be optionally decoded at different temperatures due to the wide trap distribution in Ba_0.6Sr_0.4Al₃Si₃O₄N₅:Yb²⁺. This work demonstrates highly stable oxynitride persistent phosphors with widely distributed traps show great promise in information storage, anticounterfeiting, and photodetectors.