(373s) Precision Assembly of Oppositely- and Like-Charged Nano-Objects

Walker, D. A., Northwestern University
Wilmer, C. E., Northwestern University
Kowalczyk, B., Northwestern University
Grzybowski, B. A., Northwestern University

The field of electrostatics is thought, by many, to be ?fully understood' - however at the nano-scale we continue to discover intriguing and counter-intuitive phenomena. Here we present the results from a recent fundamental study investigating the electrostatic interactions of non-spherically symmetric nanoparticles. We show, through a series of experiments supported by theoretical models, that electrostatic interactions can be used to control the assemblies of charged nano-objects with precision down to 7 nm. Specifically, we demonstrate that polarization effects and charge-induced dipoles within the metallic core of the nanoparticles can, under certain conditions, dominate the well known charge-charge interactions. Remarkably, these charge-induced dipole interactions can then mediate orientation specific aggregation between both oppositely- and like-charged particles.