Preparation of (Lu,Y) <sub>3</sub>(Al,Sc,Cr) <sub>2</sub>Al <sub>3</sub>O <sub>12</sub> phosphor ceramics with high thermal stability for near-infrared LED/LD
Yuelong Ma, Xingcan Li, Lan Wu, Chenyang Shao, Boqiang Zhang, Tao Pang, Lili Lü, Hui Qiu, Ye Tian, Guilu Wang, Yanbo Hui, Qianwen Guo, Daqin Chen
Abstract
Near-infrared (NIR) phosphor-converted light-emitting diodes/laser diodes (LEDs/LDs) are prospective lighting sources for NIR spectroscopy. However, developing NIR phosphor materials with desired thermal robustness and high photoelectric efficiency is a crucial challenge for their applications. In this work, based on the cationic radius matching effect, a series of (Lu,Y)<sub>3</sub>(Al,Sc,Cr)<sub>2</sub>Al<sub>3</sub>O<sub>12</sub> NIR phosphor ceramics (LuYScCr NIR-PCs) were fabricated by vacuum sintering. Excellent thermal stability (95%@150 ℃) was obtained in the prepared NIR-PCs, owing to their weak electron–phonon coupling effect (small Huang–Rhys factor). Being excited at 460 nm, NIR-PCs realized a broadband emission (650–850 nm) with internal quantum efficiency (IQE) of 60.68%. Combining NIR-PCs with LED/LD chips, the maximum output power of the encapsulated LED prototype was 447 mW@300 mA with photoelectric efficiency of as high as 18.6 %@180 mA, and the maximum output power of the LD prototype was 814 [email protected] A. The working temperatures of NIR-PCs were 70.8 ℃@300 mA (LED) and 102.8 ℃@3 A (LD). Finally, the prepared NIR-PCs applied in food detection were verified in this study, demonstrating their anticipated application prospects in the future.