Ultrabroadband NIR Phosphor CaMg 2 Sc 2 Ge 3 O 12 :Cr 3+ for Multifunctional Applications

Abstract In this work, the high‐efficiency broadband garnet‐structured NIR phosphor, CaMg 2 Sc 2 Ge 3 O 12 :Cr 3+ (CMSGO:Cr 3+ ), has been synthesized using a high‐temperature solid‐phase method. Under 455 nm excitation, CMSGO:Cr 3+ exhibits a red to near‐infrared (NIR) emission with an ultra‐broad range of 600–1400 nm and a maximum full width at half maximum (FWHM) of 273 nm. The Cr 3+ ions are found to occupy dodecahedral and octahedral sites in CMSGO, demonstrating good thermal stability with the emission at 375 K maintaining 72% of that at room temperature. The NIR phosphor‐converted light emitting diode (pc‐LED) combining CMSGO:Cr 3+ phosphor with a 460 nm chip exhibits excellent optical performance, an output power of 80 mW@400 mA, and a photoelectric conversion efficiency of 15.69%@20 mA. Furthermore, the vein of the hand, palm, fingers, and wrist can be clearly observed under the NIR pc‐LED device from the CMSGO:Cr 3+ phosphor. The food testing such as the fish and fruit is operated and the night vision under the NIR pc‐LED device is improved obviously. All the results demonstrate the CMSGO:Cr 3+ phosphor is an excellent candidate in the NIR pc‐LED device for rapid medical examination imaging, non‐destructive testing, and night vision.