A highly thermally stable Y3AlGa4O12:Cr3+ phosphor for near-infrared pc-LEDs†
Abstract
Highly efficient near-infrared (NIR) phosphor converted light emitting diodes (pc-LEDs) can be used in a wide range of applications such as imaging and detection. At present, a few blue LED excitable NIR phosphors have been developed producing an output power of more than 60 mW at a 100 mA input current after pc-LED packing. In this paper, we report a series of Y3AlGa4−xO12:xCr3+ (YAGG:xCr3+) phosphors with emission bands covering 650–900 nm. The Y3AlGa3.9O12:0.1Cr3+ NIR phosphor has high thermal stability, and the integrated emission intensity at 423 K is 92.36% of that at 303 K. Meanwhile, the internal quantum efficiency (IQE) of the phosphors reaches up to 88.43%. Benefiting from the efficient NIR emission of Y3AlGa3.9O12:0.1Cr3+ phosphor, the prepared NIR pc-LEDs fabricated exhibit a high output power of 67.27 mW and an impressive photoelectric conversion efficiency of 22.49% at a driving current of 100 mA, indicating its great potential for pc-LED based applications.