Efficient Lead-Free Double Perovskite Phosphors Enabled by Sb³⁺ and Gd³⁺ Co-Doping toward Plant Lighting LEDs

The development of light-emitting diodes (LEDs) that can promote the entire process of plant growth remains a challenging task. Herein, Sb³⁺ and Gd³⁺ co-doped Cs₂AgInCl₆ double perovskite microcrystals (DPMCs) with efficient red, far-red, and near-infrared (NIR) light have been synthesized by a solution-processable recrystallization method. Sb³⁺ ion doping not only regulates the emission peak position of undoped Cs₂AgInCl₆ DPMCs from 600 to 670 nm but also increases the photoluminescence quantum yields (PLQYs) by 37 times. Gd³⁺ ion doping further increases the emission intensity, resulting in a PLQY of 40.8%. This value is 81.6 times higher than that of the undoped sample. Finally, LEDs were prepared by coupling Cs₂NaInCl₆:Sb³⁺ (blue), Cs₂AgInCl₆: Sb, Gd (red, far-red, NIR) and 365 nm ultraviolet chips. The LEDs simultaneously contain blue, red, far-red, and near-infrared light emitting components, which can meet the entire process of plant growth. This work provides a new idea for the preparation of effective plant lighting LEDs.