Advances in Perovskite Nanocrystals and Nanoheterostructures: Development of Epitaxial Interfaces and Mechanistic Insights into Post-Synthesis Ion Exchanges

This PhD thesis focuses on lead halide perovskite colloidal nanocrystals: their synthesis, post-synthesis transformations, and combination with other classes of materials to form epitaxial nanocrystal heterostructures. This research unravels the previously unexplored miscibility gap in the CsPbCl3−CsPbI3 system studying the mechanism of the direct post-synthesis Cl→I exchanges in both free-standing CsPbCl3 NCs and CsPbCl3-Pb4S3Cl2 NC heterostructures. Additionally, this work sheds light on the synthetic strategies for developing the first epitaxial colloidal nanocrystal heterostructure between lead halide perovskite and lead chalcogenide addressing key challenges and showcasing its versatility in producing second-generation heterostructures through selective ion exchanges.