This week IRG-1 held a special meeting for an informal but very informational session with our international guests Ivan Infante from the Basque Center for Materials, Applications & Nanostructures and Zeger Hens from the University of Ghent who were in Seattle for MRS. Ivan shared with us his latest research and gave a talk “The Surface Chemistry of Colloidal Semiconductor Quantum Dots”. Here’s the abstract:
Despite significant progress in recent years in understanding the chemical reactions occurring on the surfaces of II-VI, III-V, and lead halide perovskite quantum dots (QDs), there are still fundamental questions that remain unanswered regarding the nature of QD surfaces, QD-ligand interactions, and the formation of trap states. Addressing these aspects is crucial for enhancing the optoelectronic efficiency of QDs. To tackle these challenges, an essential step is the utilization of first principle simulations to analyze QD surfaces. Traditional simulations have been limited by their restricted system size, typically confined to a few hundred atoms, and their focus on static properties without considering dynamic effects. In this seminar, I will present a pioneering multiscale modeling approach that combines Density Functional Theory and Molecular Dynamics simulations. This approach encompasses QDs ranging from small to real-sized QDs passivated with oleate ligands and immersed in organic solvents. Through this methodology, we gain invaluable insights into the surface characteristics and the binding energies of ligands under different experimental conditions. This methodology not only provides a deeper understanding of the intricate behavior of colloidal semiconductor nanocrystals but also paves the way for future advancements in their diverse applications.
