Broadband deep‐red‐to‐near‐infrared emission from Mn2+ in strong crystal‐field of nitride MgAlSiN3

Abstract Broadband near‐infrared (NIR) phosphors have received increasing attention for fabricating phosphor‐converted light‐emitting diodes (pc‐LEDs) as NIR light source. Most of the reported broadband NIR phosphors originate from Cr 3+ in weak crystal field environments. Herein, we report a luminescent material, MgAlSiN 3 :Mn 2+ with CaAlSiN 3 ‐type structure, demonstrating that broadband deep‐red‐to‐NIR emission can be achieved via doping Mn 2+ into crystallographic sites with strong crystal field in inorganic solids. This phosphor is synthesized via easy‐handle solid‐state reaction, and the optimized sample, (Mg 0.93 Mn 0.07 ) AlSiN 3 shows an emission band with peak at ~754 nm, FWHM of 150 nm, and internal quantum efficiency of 70.1%. The photoluminescence intensity can further be enhanced by co‐doping Eu 2+ as sensitizer. This work provides a new strategy for discovering new broadband NIR phosphors using Mn 2+ in strong crystal field as luminescence center.