posted on 2022-03-22, 15:09authored byLipeng Jiang, Xue Jiang, Yan Zhang, Changxin Wang, Pei Liu, Guocai Lv, Yanjing Su
Ce-doped
garnet phosphors play an important role in the white light-emitting
diode (LED) family. In the past years, a lot of trial-and-error experiments
guided by experience to discover phosphors suitable for white LEDs
have been presented. The working temperature of phosphors may reach
200 °C in white LEDs, and so, the exploration of phosphors with
excellent thermal stability at the desired wavelength continues to
be a challenge. In the present study, to discover novel cyan–green
garnet:Ce phosphors, wavelength and thermal stability machine learning
models were built by constructing reasonable features. Among the 171,636
compounds with garnet structures predicted by our models, 25 samples
were selected for preparation and characterization by multiobjective
optimization based on active learning. Lu1.5Sr1.5Al3.5Si1.5O12:Ce performed the best
with excellent thermal stability (≥60% emission intensity was
retained at 640 K) and exhibited emission peaks of about 505 nm, and
it is a very promising phosphor for future applications, especially
in high-temperature operating environments.