Theoretical and Experimental Investigation of the Ligand‐Directed Assembly and Photovoltaic Performance of PbSe Nanorods

Abstract PbSe nanorods (NRs), featuring notable multiple exciton generation yield, are considered as one of the most promising nanoparticles for the solar energy field. In this respect, fundamental understanding of the PbSe NR‐ligand interactions is of great importance for the successful integration of the PbSe NRs into the solar cells. This study discloses the structure‐NR property relationship of the widely used ligands, 1,2‐ethanedithiol (EDT) and 1,3‐benzenedithiol (BDT). In agreement with the microscopy imaging experiments, semiempirical calculations, and Molecular Dynamics simulations show that the PbSe NRs decorated with the EDT molecules exhibit stronger interfacial interactions due to the interdigitation of the EDT ligands at the interface. Owing to the reduced interlayer distances and enhanced coplanarity of the NR surfaces, solar cells based on well‐ordered EDT‐treated PbSe NRs exhibit 75% higher photocurrent and 58% higher open circuit voltage compared to the cells based on the BDT treated PbSe NRs. It is believed that this study combining computational and experimental data will provide a detailed understanding of the NR‐ligand interactions governing the photophysical and optoelectronic properties of the materials and will have a remarkable impact on mastering the PbSe NR surface in the near future.