High‐Power Broadband NIR LEDs Enabled by Highly Efficient Blue‐to‐NIR Conversion

Phosphor‐converted light‐emitting diodes (pc‐LEDs) with broadband near‐infrared (NIR) emission have emerged as compact light sources for portable NIR spectroscopy. However, the associated broadband NIR phosphors suffer from low quantum efficiency (QE) and severe thermal quenching. Here the realization of highly efficient (internal QE ≈ 90%) and nearly zero‐thermal‐quenching broad NIR emission in Cr3+ and Yb3+ codoped Gd3Sc1.5Al0.5Ga3O12 (GSGG) via efficient energy transfer from Cr3+ to Yb3+ is reported, whereby a high‐performance NIR pc‐LED is obtained that can generate ultra‐broad‐band NIR emission covering the whole range of 700−1100 nm with high output power (50 mW at a current of 100 mA) and high photoelectric efficiency (24% at a current of 10 mA). The results not only demonstrate that Cr3+ and Yb3+ codoped GSGG has great potential for compact NIR light sources, but also indicate that the strategy of energy transfer can be exploited for developing new NIR phosphors with both high QE and thermal stability.