Efficient open-air synthesis of Mg²⁺-doped CsPbI₃ nanocrystals for high-performance red LEDs

Inorganic CsPbI₃ perovskite nanocrystals (NCs) exhibit remarkable optoelectronic properties for illumination. However, their poor stability has hindered the development of light-emitting diodes (LEDs) based on these materials. In this study, we propose a facile method to synthesize Mg²⁺-doped CsPbI₃ NCs with enhanced stability and high photoluminescence (PL) intensity under ambient air conditions. Theoretical calculations confirm that doped NCs possess stronger formation energy compared to undoped NCs. The undoped CsPbI₃ NCs emit red light at approximately 653 nm. We optimize the doping ratio to 1/30, which significantly enhances the photoluminescence of single-particle CsPbI₃ NCs. Subsequently, we fabricate a red LED by combining the CsPbI₃ NCs with a blue chip. The resulting LED, based on the doped CsPbI₃ NCs, exhibits excellent performance with a high luminance of 4902.22 cd m^-2 and stable color coordinates of (0.7, 0.27). This work not only presents a simple process for synthesizing perovskite NCs but also provides a design strategy for developing novel red LEDs for various applications.