A Blue-Light-Emitting 3 nm-Sized CsPbBr₃ Perovskite Quantum Dot with ZnBr₂ Synthesized by Room-Temperature Supersaturated Recrystallization

Recently, tuning the green emission of CsPbBr₃ quantum dots (QDs) to blue through quantum size and confinement effects has received considerable attention due to its remarkable photophysical properties. However, the synthesis of such a blue-emitting QD has been challenging. Herein, supersaturated recrystallization was successfully implemented at room temperature to synthesize a broadband blue-emitting ZnBr₂-doped CsPbBr₃ QD with an average size of ~3 nm covering the blue spectrum. The structural and optical properties of CsPbBr₃ QDs demonstrated that QD particle size may decrease by accommodating ZnBr₂ dopants into the perovskite precursor solution. Energy-dispersive spectroscopy confirmed the presence of zinc ions with the QDs. This work provides a new strategy for synthesizing strongly quantum-confined QD materials for photonic devices such as light-emitting diodes and lighting.