Enhanced broadband near-infrared emission based on cation substitution in Cr3+ ion doped YGdScSbO7 phosphor

Cr 3+ -activated near-infrared (NIR) phosphors have attracted significant attention in recent years owing to their potential applications in nondestructive testing, bioimaging, and night vision technologies. However, the development of high-performance NIR phosphors remains a considerable challenge. In this work, a novel broadband NIR-emitting phosphor, YGdScSbO 7 : Cr 3+ , was successfully synthesized via a high-temperature solid-state reaction. The obtained phosphor exhibits a strong emission centered at 763 nm with a full width at half maximum (FWHM) of 142 nm. Inspired by the cation substitution strategy, the partial substitution of Sc 3+ with Ga 3+ ions significantly improves the emission intensity and quantum efficiency. The optimized sample, YGdScSbO 7 : 0.03Cr 3+ , 0.8Ga 3+ , shows a broadband NIR emission covering the 600–950 nm region with a FWHM of 117 nm and an internal quantum efficiency as high as 73.89%. Furthermore, the sample maintains approximately 56.64% of its initial emission intensity at 363 K, indicating great thermal stability. A NIR phosphor-converted LED (pc-LED) fabricated by the optimized phosphor with a 450 nm blue LED chip delivers an output power of 8 mW under the 180 mA driving current, demonstrating promising potential for applications in night vision illumination, nondestructive inspection, and biomedical imaging.