Efficient Near‐Infrared Luminescence in Lanthanide‐Doped Vacancy‐Ordered Double Perovskite Cs<sub>2</sub>ZrCl<sub>6</sub> Phosphors via Te<sup>4+</sup> Sensitization
Jinyue Sun, Wei Zheng, Ping Huang, Meiran Zhang, Wen Zhang, Zhonghua Deng, Shaohua Yu, Mengyao Jin, Xueyuan Chen
Abstract
Abstract All‐inorganic lead‐free perovskite‐derivative metal halides have shown great promise in optoelectronics, however, it remains challenging to realize efficient near‐infrared (NIR) luminescence in these materials. Herein, we report a novel strategy based on Te 4+ /Ln 3+ (Ln=Er, Nd, and Yb) co‐doping to achieve efficient NIR luminescence in vacancy‐ordered double perovskite Cs 2 ZrCl 6 phosphors, which are excitable by a low‐cost near‐ultraviolet light‐emitting diode (LED) chip. Through sensitization by the spin‐orbital allowed 1 S 0 → 3 P 1 transition of Te 4+ , intense and multi‐wavelength NIR luminescence originating from the 4f→4f transitions of Er 3+ , Nd 3+ , and Yb 3+ was acquired, with a quantum yield of 6.1 % for the Er 3+ emission. These findings provide a general approach to achieve efficient NIR emission in lead‐free metal halides through ns 2 ‐metal and lanthanide ion co‐doping, thereby opening up a new avenue for exploring NIR‐emitting perovskite derivatives towards versatile applications such as NIR‐LEDs and bioimaging.