Directing the assembly of gold nanoparticles with two-dimensional molecular networks.

Lamellar patterns resulting from the adsorption of p-dialkoxybenzene derivatives on HOPG have been investigated as molecular templates for directing the assembly of thiol-capped gold nanoparticles (AuNP). STM characterization at the liquid-solid interface reveals the periodic arrangement of AuNP on top of the self-assembled molecular network (SAMN), spanning hundreds of nanometers. The resulting superlattices are notably different from the close-packed structures formed by spherical nanoparticles during evaporative drying. The templating effect is based on van der Waals interactions of the alkyl chains of the SAMN and AuNP, and the assembly efficiency is greatest when these chains are of similar length.