Tunable near-infrared phosphor LiScSbO:Cr by Mg substitution and Yb co-doping for phosphor-converted light-emitting diodes

Near-infrared (NIR) phosphors have been extensively used in the fields of biological imaging, night vision monitoring, and food safety inspection. Although Cr 3+ doping phosphors have been widely reported, achieving broadband and tunable NIR emissions remains challenging. In this work, Cr 3+ -doped LiSc 2 SbO 6 broadband NIR phosphors were synthesized by a high-temperature solid-phase method. LiSc 2 SbO 6 :Cr 3+ exhibits a wide emission band of 780-1400 nm. By [Mg 2+ -Mg 2+ ] co-substituting the [Li + -Sc 3+ ] chemical units, controllable emission is achieved with the emission peak tuning in the range of 890-950 nm, FWHM in the range of 215-239 nm, and the maximum intensity increased by 1.51 times. On co-doping with Yb 3+ ions, the luminous intensity of the Li 0.7 Mg 0.6 Sc 1.7 SbO 6 :0.02Cr 3+ ,0.05Yb 3+ (LMSS:Cr 3+ ,Yb 3+ ) phosphor has been further enhanced by 5.62 times. Thus, the LMSS:Cr 3+ ,Yb 3+ phosphor has great potential in the field of anti-counterfeiting and information encryption. By combining LMSS:Cr 3+ ,Yb 3+ with a commercial blue LED chip, the obtained NIR pc-LED performs well in night vision and non-destructive testing applications. The NIR pc-LED prepared with LMSS:Cr 3+ ,Yb 3+ performed well in night vision, nondestructive testing, multiple anti-counterfeiting and information encryption technologies.