Unraveling the Defect‐Induced Spectral Tuning in a Ce‐Doped Garnet Solid‐Solution Phosphor
Yonghong Qin, Yaxin Cao, Lixin Ning, Xicheng Wang, Yuhua Wang
Abstract
Abstract The increasing demand for white light‐emitting diode (WLED) has prompted the development of phosphors, in which Ce 3+ ‐activated garnet has been representative and widely investigated. The optimization and improvement of performance have long been a focus in the phosphor area. However, the trade‐off of phosphor performance always exists and is difficult to satisfy simultaneously, thereby necessitating a better understanding of the design principles that tune spectra performance comprehensively. Herein, the defect‐induced spectral tuning mechanism in a Ce‐doped garnet solid‐solution phosphor Ca 1.5‐ x Y 1.5+ x Al 3.5+ x Si 1.5‐ x O 12 :Ce 3+ (CYAS:Ce 3+ ) is promoted. The enhancement of luminescence intensity and thermal stability together with red‐shift of emission can be achieved by chemical unit co‐substitution of [Y 3+ ‐Al 3+ ] for [Ca 2+ ‐Si 4+ ], which originated from the increasing anti‐site vacancy. The related mechanism is fully elucidated by combining structural and spectral analysis with density functional theory (DFT) calculations. This study provides a subtle control for the performance‐tuning of phosphors, which can deepen the understanding of the design principle inside‐out and the subsequent development and exploration of novel optoelectronic functional materials.