Ligand Engineering Achieves Suppression of Temperature Quenching in Pure Green Perovskite Nanocrystals for Efficient and Thermostable Electroluminescence

• Innovative room-temperature synthesis of pure green FAPbBr3 nanocrystals using aromatic amine ligands (PEA or 3-F-PEA) yields high-quality crystals with uniform size and reduced long-chain ligands. • Ligand engineering effectively suppresses thermal quenching in organic-inorganic hybrid FAPbBr3 nanocrystals, preserving over 90% of room-temperature photoluminescence at 380 K. • The resulting FAPbBr3-based light-emitting diodes achieve a peak external quantum efficiency of 21.9% at room temperature and maintain less than 10% efficiency loss at 343 K. • This work provides a novel strategy for developing thermostable perovskite nanocrystals, advancing their practical application in displays and lighting.