On the optimisation of the broadband NIR emitter LiScO2:Cr3+

Cr3+-activated LiScO2 has emerged as a promising near-infrared (NIR) phosphor with potential applications in medical and optical technologies. In this study, the luminescence properties of LiScO2:Cr3+ were optimised through systematic cation substitutions. The effect of Cr3+-concentration (0.5 to 5 mol.%) was investigated, along with substitutions of Sc3+ by Al3+ and Li+ by Na+. The synthesised phosphors were characterised upon using X-ray diffraction (XRD), reflectance spectroscopy, fluorescence spectroscopy, and decay curve analysis. The results demonstrate that optimal Cr3+ doping concentrations enhance NIR emission, whereas excessive doping leads to concentration quenching. Substitutions of Sc3+ with Al3+ and Li+ with Na+ impact crystal field strength and luminescence properties. These findings contribute to the development of efficient broadband NIR phosphors for future applications.