Efficient NIR-II luminescence in the double-perovskite Li3Mg2SbO6:Ni2+ phosphor for spectroscopy applications

Phosphors with emission in the second near-infrared (NIR) bio-window (1000 nm-1700 nm) have promising applications in bio-imaging, food quality analysis, and nondestructive examination. However, developing an efficient NIR phosphor in this emission range is a significant challenge. Herein, we report a perovskite-like Li₃Mg₂SbO₆:Ni²⁺ phosphor, which exhibits a broadband NIR emission peaking at 1380 nm and a full width at half maximum (FWHM) of 281 nm under near-ultraviolet 395 nm excitation. The optimized sample, Li₃Mg_1.985SbO₆:0.015Ni²⁺, demonstrates a rarely high internal quantum efficiency (IQE = 87.1%). Furthermore, multifunctional applications of the fabricated device were realized, demonstrating the excellent practicability of this material.