Controllable Colloidal Synthesis of MAPbI3 Perovskite Nanocrystals for Dual-Mode Optoelectronic Applications

This study demonstrates an acetate ligand (AcO–)–assisted strategy for the controllable and tunable synthesis of colloidal methylammonium lead iodide (MAPbI3) perovskite nanocrystals (PNCs) for efficient photovoltaic and photodetector devices. The size of colloidal MAPbI3 PNCs can be tuned from 9 to 20 nm by changing the AcO–/MA ratio in the reaction precursor. In situ observations and detailed characterization results show that the incorporation of the AcO– ligand alters the formation of PbI6 octahedral cages, which controls PNC growth. A well-optimized AcO–/MA ratio affords MAPbI3 PNCs with a low defect density, a long carrier lifetime, and unique solid-state isotropic properties, which can be used to fabricate solution-processed dual-mode photovoltaic and photodetector devices with a conversion efficiency of 13.34% and a detectivity of 2 × 1011 Jones, respectively. This study provides an avenue to further the precisely controllable synthesis of hybrid PNCs for multifunctional optoelectronic applications.