Roles of ligand and solvent for CsPbBr3 nanoplatelets

CsPbBr3 nanoplatelets (NPLs) have been considered as a promising candidate in the field of blue-emitting because of large exciton binding energies, thickness-tunable emission and excellent charge-transfer properties. In this paper, the effect of ligand concentration, solvent polarity, and ligand hydrocarbon chain on the photo-luminescence (PL) and morphology properties of NPLs were studied. The PL properties of the NPLs depended strongly on the thickness which was controlled by ligands. The thickness of NPLs increased with increasing the amount of oleylamine. In contrast, the addition amount of oleic acid did not affect the PL properties of the NPLs. In addition, the thickness of NPLs becomes thinner with shortening carbon chain. Furthermore, the polarity of solvent (n-hexane instead of toluene) played an important role in the thickness of NPLs. The higher polarity of toluene induces the preparation of thicker NPLs. These results contribute to the further study of the formation mechanism of perovskite NPLs and promote the application of NPLs in the field of optoelectronic devices.