Formation and Near-Infrared Emission of CsPbI Nanoparticles Embedded in CsPbI Crystals.

CsPbI, as a rarely investigated member of the CsPbX (X is a halogen element) family, has been successfully synthesized at low temperatures, and the synthetic conditions have been optimized. Metal iodides such as LiI, KI, NiI, CoI, and ZnI, as additives, play an important role in enhancing the formation of the CsPbI microcrystals. ZnI with the lowest dissociation energy is the most efficient additive to supply iodide ions, and its amount of addition has also been optimized.