Electrophoretic Deposition of Spherical and Rod-Shaped Nanocrystals into Close Packed Superlattices

Ordered nanocrystal assemblies are an exciting new class of materials where electronic, optical or magnetic properties can be dictated by tuning the position and ligand environment of each nanocrystal structural unit. Device integration in both nanoelectronics and nanophotonics relies on the ability to locate these ensembles with nanoscale accuracy exactly where they are needed. In this paper we overview our recent work in the area of electrophoretic deposition of charged nanocrystals from toluene.(1, 2) The systems discussed are twofold 1: gold nanocrystals (8 nm) which are positively charged and assembled from a toluene solution with unprecedented selectivity into lithographic channels and 2: CdS nanorods (100 nm × 8 nm) which are negatively charged and assembled into perpendicularly oriented nanorod superlattices over centimeter squared areas suitable for nanorod solar-cells.