<p>This study demonstrates the X-ray-activated near-infrared persistent luminescence in Li₂Ge₇O₁₅:Cr³⁺ phosphors by the high-temperature solid-phase method. The influence of Cr³⁺ doping concentration on the structure, morphology and luminescent characteristics of the synthesized material was systematically investigated through X-ray diffraction (XRD), scanning electron microscopy (SEM), fluorescence spectroscopy, and persistent luminescence spectral analysis. The XRD result showed that the synthesized samples were pure. Under X-ray irradiation, the sample Li₂Ge₇O₁₅:Cr³⁺ exhibited near-infrared persistent luminescence and photo stimulated luminescence. The photoluminescence and afterglow emission peaks were located at 699.8 nm, which was due to the ²E→⁴A₂ of Cr³⁺. The optimal Cr³⁺ doping concentration was determined to be 0.05 %, at which the material demonstrated remarkable persistent luminescence performance. Notably, even if exposed to X-ray irradiation only for 5 s, the sample maintained exceptional near-infrared persistent emission characteristics lasting over 30 minutes. Furthermore, the material exhibited exceptional photostimulated luminescence (PSL) characteristics, with its near-infrared afterglow intensity being remarkably amplified under 980 nm laser irradiation. Thermoluminescence (TL) spectral analysis revealed the existence of multiple discrete trap energy levels within the host matrix, whose activation behavior was dependent on the excitation source. Under X-ray irradiation, the sample generated an additional effective trap level, which was more conducive to storing excitation energy. These results suggested that Li₂Ge₇O₁₅:Cr³⁺ was a potential X-ray-induced near-infrared persistent luminescent material.</p> Graphical Abstract <p></p>