Because of its high photoluminescence external quantum efficiency (PLQY), excellent fluorescence characteristics and good phase stability, perovskite nanocrystals have advantages in LED, backlight display, ion radiation detection and imaging, catalysis and color conversion. Good application. Perovskite nanocrystalline devices still have stability problems, and even in an inert atmosphere, they will hinder the improvement of device performance. The instability of nanocrystals stems from the difference in the interaction between body atoms and surface atoms and ligands. Surface ligand engineering can control the interaction between nanocrystals and ligands. As an ideal perovskite nanocrystal, it should have high PLQY, low defect state density and good long-term stability. Therefore, the development of low-cost, high-throughput and high-quality synthesis strategies for perovskite nanocrystals is a huge challenge and urgent need.

     Here, the team of Professor Fang Guo of Wuhan University proposed a room temperature diffusion-induced extraction crystallization (DEC) method, in which silicone oil is used as a medium to separate the solvent from the perovskite precursor and diethyl ether to promote nucleation to form highly fluorescent perovskite Mine NCs. The prepared NCs have a PLQY of more than 90%. The DEC method strengthens the interaction between ligands and NCs through hydrophobic silicone oil. Therefore, after aging in the air for more than 7 months, NCs can maintain 95% of the initial PLQYs. This discovery is of great significance for the further study of high PLQY perovskite NCs.