Controllable emission bands and morphologies of high-quality CsPbX₃ perovskite nanocrystals prepared in octane

Halide perovskite (CsPbX₃, X = Cl, Br, or I) quantum dots have received increasing attention as novel colloidal nanocrystals (NCs). Accurate control of emission bands and NC morphologies are vital prerequisites for most CsPbX₃ NC practical applications. Therefore, a facile method of synthesizing CsPbX₃ (X = Cl, Br, or I) NCs in the nonpolar solvent octane was developed. The process was conducted in air at ~ 90 ℃ to synthesize high-quality CsPbX₃ NCs showing 12–44 nm wide emission and high photoluminescence quantum yield, exceeding 90%. An in situ anion-exchange method was developed to tune CsPbX₃ NC photoluminescence emission, using PbX₂ dissolved in octane as the halide source. NC morphology was controlled by dissolving specific metal–organic salts in the precursor solution prior to nucleation, and nanocubes, nanodots, nanosheets, nanoplatelets, nanorods, and nanowires were obtained following the same general method providing a facile, versatile route to controlling CsPbX₃ NC emission bands and morphologies, which will broaden the range of CsPbX₃ NC practical applications.