Trap‐Engineering the Persistent Luminescence of Ca3Ga4O9:Tb3+ via Al3+ Substitution for Optical Data Storage

Abstract

AbstractOptically stimulated luminescence (OSL) materials hold great potential for optical data storage (ODS) and anticounterfeiting applications. Nevertheless, the scarcity of suitable luminescent materials with deep‐level traps remains a significant obstacle. Herein, a host substation strategy have been employed to tune the persistent luminescence (PersL) and OSL properties of Ca3Ga4O9:Tb3+ by Al3+ substitution through trap engineering and demonstrated their potential. Specifically, the photoluminescence of the Ca2.985(Ga1‐y%Aly%)4O9:0.5%Tb3+ of Tb3+ is first investigated due to its different occupancies of Ca2+. The influence of host substitution on the crystal structure, trap depth, trap density, PersL, and OSL properties have further investigated. A series of strong PersL and OSL peaks from the Ca2.985(Ga1‐y%Aly%)4O9:0.5%Tb3+ with bluish‐green emissions have been observed. The Ca2.985(Ga1‐y%Aly%)4O9:0.5%Tb3+ have shown controllable photon release upon thermal and optical stimuli, enhancing their performance for ODS. Thermally stimulated luminescence suggests that vacancy and defect concentrations inside the Ca3‐x%(Ga1‐y%Aly%)4O9:x%Tb3+ can be manipulated by Tb3+ doping and Al3+ substitution, which ultimately leads to the formation of deep traps and a broad distribution of traps with increased deep trap concentration. The work demonstrates that trap engineering through Al3⁺ substitution is an effective method for tuning PersL and OSL properties of Ca2.985(Ga1‐y%Aly%)4O9:0.5%Tb3+ for ODS.