Filling the 820-880 nm gap of Fe³⁺-activated efficient near-infrared phosphor toward versatile applications

Fe³⁺ ion as an activator with eco-friendly nature has an exceptional ability to achieve efficient near-infrared (NIR) luminescence within 700-1100 nm range. However, its emission in 820-880 nm region is rarely reported, limiting the versatile applications of Fe³⁺-activated materials. In this Letter, a double-perovskite KLaMgTeO₆:Fe³⁺ phosphor was developed, which exhibits an emission peak centered at 851 nm, accompanied by a high photoluminescence quantum yield (PLQY) of up to 82%. Furthermore, the fabricated NIR light source demonstrated excellent performance in night-vision, imaging, and non-destructive testing applications. Thus, this study offers an efficient NIR material that covers a previously underexplored emission window, expanding the application landscape of Fe³⁺-doped materials.