Past Event: Oden Institute Seminar

Exploring Charge Transport and Energy Conversion at the Nanoscale with Computation

Jeffrey B. Neaton,

Abstract

Nanostructures are often distinguished by their large surface-to-volume ratios that, upon integration into devices, can lead to a high density of nanoscale interfaces. The impact of these interfaces on device function is not yet well understood, particularly in the area of solar energy conversion. In this talk, I will describe new computational methods, based on first-principles density functional theory and beyond, that have advanced our understanding of electronic structure at nanoscale metal-organic interfaces. Specific examples to be discussed are recent collaborations with experiment, centering on the conductance, thermopower, and mechanically-controlled switching of amine- and pyridine-linked single-molecular junctions—small molecules interfaced with macroscopic gold electrodes by amine and pyridine endgroups. These studies have provided a unique opportunity to verify and validate standard first-principles methods while quantitatively exploring fundamental mechanisms of charge transport and energy conversion at the molecular scale. Future plans to simulate light-matter interactions in these systems will be discussed briefly, with applications to solar energy conversion in organic photovoltaics, and surface-enhanced Raman scattering in nanoplasmonics. This work is supported by: DOE through the Molecular Foundry, Helios, and PECASE; DARPA; and NSF through the Network for Computational Nanoscience.