Wafer‐Scale MgO:Li ⁺ ,Cr ³⁺ Transparent Ceramic Scintillators With NIR Emission for X‐Ray Dual‐Mode Fusion and Time‐Lapse Imaging

ABSTRACT The integration of X‐ray and near‐infrared (NIR) imaging holds great potential for nondestructive detection and biomedical analysis. However, premature carrier recombination leads to the loss of imaging information, and the development of reliable transparent scintillators with exceptional light yield (LY) remains a challenge. Here, we report a wafer‐scale bifunctional MgO:Li + ,Cr 3+ NIR‐transparent ceramic with a diameter of 45 mm. Under 460 nm blue light and X‐ray excitation, the ceramic exhibits a narrow emission peak at 722 nm with a broad shoulder at 750 nm. The LY and detection limit are determined to be 25683 Ph·MeV −1 and 0.84 µGy·s −1 , respectively. Notably, oxygen vacancy‐related deep traps in the MgO:Li + ,Cr 3+ ceramic enable efficient electron storage and persistent luminescence exceeding 120 min. Fused X‐ray and NIR dual‐modal imaging enables clear visualization for the profile of a concealed soft robot. Its in situ localization through 5 mm‐thick pork tissue is achieved via X‐ray‐activated persistent luminescence, which demonstrates the transformative potential of the MgO:Li + ,Cr 3+ ceramic for advanced biomedical and industrial inspection applications.