ADSORPTION OF SILVER COLLOIDAL PARTICLES THROUGH COVALENT LINKAGE TO SELF-ASSEMBLED MONOLAYERS

Self-assembled monolayers of a small bifunctional molecule (4-carboxyt hiophenol) have been formed on Al and Au surfaces. The nature of coord ination of the molecules to the two metal surfaces is different, leadi ng to different terminal functionality of the monolayer surface. This aspect has been favorably exploited to self-assemble Ag particles from a colloidal solution on the monolayer-covered Al surface which is thi ol rich. The self-assembly of the Ag particles does not take place on the monolayer-covered Au surface with carboxylic acid surface function ality. The adsorption of the monolayer on Al and Au surfaces and Ag co lloidal particles on the self-assembled monolayer has been followed us ing electron microscopy, quartz crystal microbalance, and X-ray photoe mission measurements. The two-dimensional array of strongly bonded met al nanoparticles shows potential for application as metal-supported ca talysts and sensors, generation of submicrometer electronic devices, h igh density data storage, etc.