Intrinsic Chiroptical Evolution in Perovskite Nanocrystals.

Here, we observed chiroptical evolution during the synthesis of perovskite nanocrystals (NCs). Using a steric-delayed nucleation strategy, we slowed the ripening of NCs and observed changes in the circular dichroism (CD) signal of perovskite NCs. Two chiroptical evolution events occurred during NC formation under different conditions, attributed to ligand displacement and NC self-assembly, respectively. Surface characterization and computational studies demonstrate that the ligands initially bind to the NC surface and dissociate during the ripening stage, offering the time window to observe and enhance the intrinsic chirality. Our findings provide a new strategy for studying and designing intrinsically chiral perovskite nanostructures.