Highly Stable Oxynitride Persistent Phosphors with Widely Distributed Traps for Information Storage and Anticounterfeiting
Ying Lv, Ning Zhao, Wuqiang Li, Cunjian Lin, Changjian Chen, Jumpei Ueda
Abstract
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 0.58 Sr 0.4 Al 3 Si 3 O 4 N 5 :0.02Yb 2+ (Ba 0.6 Sr 0.4 Al 3 Si 3 O 4 N 5 :Yb 2+ ) 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 0.6 Sr 0.4 Al 3 Si 3 O 4 N 5 :Yb 2+ 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 0.6 Sr 0.4 Al 3 Si 3 O 4 N 5 :Yb 2+ 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 0.6 Sr 0.4 Al 3 Si 3 O 4 N 5 :Yb 2+ . This work demonstrates highly stable oxynitride persistent phosphors with widely distributed traps show great promise in information storage, anticounterfeiting, and photodetectors.