Synergetic effect of the surface ligand and SiO2 driven photoluminescence stabilization of the CH3NH3PbBr3 perovskite magic-sized clusters

Zero-dimensional Perovskite Magic-size Clusters play crucial roles in understanding and controlling nucleation and growth of semiconductor nanoparticles. However, their metastability behavior is a critical hindrance for reliable characterizations. Here, we report the first demonstration of using an excess amount of surface ligand and SiO2 as novel passivation for synthesizing the magic-sized clusters (MSCs) by the Ligand-assisted reprecipitation method. A synergetic effect between an excessed surface ligand and SiO2 inhibits the protonation and deprotonation reaction between amine-based and acid-based ligand, leading to enhanced PL stability. The obtained CH3NH3PbBr3 PMSCs/SiO2 retain 70% of its initial emission intensity in ambient conditions for 20 days. This passivation approach opens an entirely new avenue for the reliable characterizations of CH3NH3PbBr3 PMSCs, which will significantly broaden their application for understanding and controlling nucleation and growth of semiconductor nanoparticles.