High Quantum Efficiency Broadband Near-Infrared LaTiSbO6:Cr3+ Phosphors

Cr3+ doped phosphor shows great potential for near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs). However, low quantum efficiency have severely restricted NIR pc-LED performance. Herein, a novel Cr3+-doped broadband NIR LaTiSbO6 (LTS) phosphor was developed. The LTS:0.6%Cr3+ phosphor achieves an outstanding internal quantum efficiency of 91.82%. The photoluminecence spectrum shows a broad emission of 650–1300 nm centered at 832 nm with a large full width at half maximum (FWHM) of 183 nm and an R-line emission of 710 nm. Meanwhile, the optimal LTS:0.6%Cr3+ phosphor maintains 64.72% of its initial intensity at 373 K. A prototype NIR pc-LED was fabricated with LTS:Cr3+ to evaluate its potential practical application, which reveals an NIR output power of 202 mW at 100 mA and 680 mW at 300 mA, photoelectric efficiencies of 3.21% at 100 mA and 1.85% at 300 mA. The results demonstrate that the high-performance LTS:Cr3+ phosphors have great potential for applications in broadband NIR pc-LEDs.