An efficient and thermally stable near-infrared phosphor derived from the Ln<sub>3</sub>ScInGa<sub>3</sub>O<sub>12</sub>:Cr<sup>3+</sup> (Ln = La, Gd, Y, and Lu) garnet family
Zurong Liao, Chaojie Li, Jiyou Zhong, Yang Li, Weiren Zhao
Abstract
-doping concentration of 6 mol% exhibits a high internal quantum efficiency (IQE = 83.1%) and excellent absorption efficiency (AE = 44.2%) under 450 nm blue light excitation, enabling an external quantum efficiency as high as 36.7%. Moreover, this material can maintain 93.0% of the initial intensity when heated up to 423 K, implying outstanding thermal stability. Finally, a prototype NIR pc-LED device was fabricated by coating the optimized phosphor on a 455 nm LED chip, which generates a broadband NIR emission with a peak located at 765 nm and a full width at half maximum of 127 nm. The NIR output power and NIR photoelectric conversion efficiency of this device were found to be 38.01 mW and 11.0%, respectively, under 100 mA driving current, demonstrating the feasibility of this material to be applied in NIR pc-LEDs.