A Novel Near‐Infrared Emitting Sr₂LuSbO₆:Fe³⁺ Phosphor with Persistent Luminescence Performance

Abstract The near‐infrared (NIR) persistent luminescence (PersL) materials have attracted widespread attention owing to the unique self‐sustained light with good penetrability. Currently, most of the reported NIR PersL materials are activated by Cr³⁺. Considering the potential toxicity of chromium ions, there is an urgent requirement to explore the Cr³⁺‐free NIR phosphors. Herein, a novel NIR phosphor Sr₂LuSbO₆:Fe³⁺ (SLSO:Fe³⁺) is prepared and its luminescence properties are systematically studied. The Fe³⁺‐activated Sr₂LuSbO₆ exhibits a long‐wavelength NIR emission band centered at 890 nm with a 110 nm full‐width at half maximum (FWHM), and its PersL can last over 18 h. The phosphor shows excellent PersL stability even after being dispersed in solutions of different environments for 7 days. Furthermore, the PersL emitted by the phosphor can penetrate the 2 cm thickness beef, evidencing its good NIR PersL penetration property. This work provides a novel NIR PersL materials based on Fe³⁺ luminescence for technological applications and also contributes to accelerate the development of new‐generation Fe³⁺‐doped NIR PersL phosphor toward versatile applications.