Tunable dual-emission of Sb<sup>3+</sup>, Ho<sup>3+</sup> Co-doped Cs<sub>2</sub>NaScCl<sub>6</sub> single crystals for light-emitting diodes
Qingyong Qin, Yu Liu, Ge Gao, Zhaoqiong Chen, Zejiang Gao, Li Chen, Xian-Ci Zhong, Bingsuo Zou
Abstract
Abstract Lead-free halide double perovskites are considered as one of the most promising materials in optoelectronic devices, such as solar cells, photodetectors, and light-emitting diodes (LEDs), due to their environmental friendliness and chemical stability. However, the extremely low photoluminescence quantum yield (PLQY) of self-trapped excitons (STEs) emission from lead-free halide double perovskites impedes their applications. Herein, Sb 3+ ions were doped into rare-earth-based double perovskite Cs 2 NaScCl 6 single crystals (SCs), resulting in a large enhancement of PLQY from 12.57% to 87.37%. Moreover, by co-doping Sb 3+ and Ho 3+ into Cs 2 NaScCl 6 SCs, the emission color can be tuned from blue to red, due to an efficient energy transfer from STEs to Ho 3+ ions. Finally, the synthesized sample was used in multicolor LED, which exhibited excellent stability and optical properties. This work not only provides a new strategy for improving the optical properties of Cs 2 NaScCl 6 SCs, but also suggests its potential application in multicolor LEDs.