A novel broadband near‐infrared Ca ₂ Y ₃ Sb ₃ O ₁₄ : Cr ³⁺ rhombohedral pyrochlores phosphor and its application in pc‐LEDs

Abstract

Abstract Recently, there has been a growing demand for broadband near‐infrared (NIR) phosphor. The paper proposes a novel Cr 3+ doped Ca 2 Y 3 Sb 3 O 14 phosphor through basic research of Ca 2 Ln 3 Sb 3 O 14 : Cr 3+ (Ln = Sc, Lu, and Y) phosphor. Under 467 nm excitation, Ca 2 Y 3 Sb 3 O 14 : Cr 3+ phosphor shows a broad NIR emission band (650–950 nm) centered at 776 nm with a full width at half‐maximum of 110 nm. The optimal Cr 3+ doping concentration is 0.05, with an internal quantum efficiency of 78%. Meanwhile, the photoluminescence emission intensity at 373 K remains 61.3% of that at room temperature. Using phosphor‐in‐glass technology, a glass–ceramic plate showed a slight improvement in its thermal stability compared to the pure phosphor. Combining Ca 2 Y 3 Sb 3 O 14 : 0.05Cr 3+ phosphor with a commercial blue‐light‐emitting chip presents an output power of 44.51 mW with a photoelectric conversion efficiency of 14.78% at a drive current of 100 mA. These results suggest that the Ca 2 Y 3 Sb 3 O 14 : Cr 3+ phosphor has great potential in the pc‐light‐emitting diodes.