High thermally stable deep red-emitting Sb3+,Ho3+-codoped Cs2NaScCl6 double perovskite for plant lighting

Lead-free halide double perovskite has received widespread attention due to its excellent optical performance. However, the lack of deep red light and poor heat quenching resistance severely limit its application in plant lighting field. In this work, Ho3+ was introduced into the thermally stable Cs2NaScCl6 host, exhibiting a deep red emission of 660 nm. By constructing an energy transfer channel between Sb3+ and Ho3+, the photoluminescence quantum yield (PLQY) of Cs2NaScCl6:1%Sb3+,40%Ho3+ rises up to 53.8%, that is increased by 17 times, and its emission intensity can still be maintained by 80% at 423 K, exhibiting good heat quenching resistance. The obtained Cs2NaScCl6:1%Sb3+,40%Ho3+ and Cs2NaScCl6:1%Sb3+ with blue light emission were employed for fabricating a light-emitting diode (LED) device with a 340 nm UV chip, and its emission spectrum matches well the absorption spectra of chlorophyll A and chlorophyll B with the high resemblance of 70% and 75%, making it suitable for use as an artificial light source to control the growth process of plants in the field of plant lighting.