Investigating catalytic properties of composite nanoparticle assemblies

We present herein recent findings of an investigation of catalyst assembly and activation using metallic nanoparticles encapsulated with organic monolayers. Gold nanocrystals (2-5 nm) encapsulated with thiolate monolayers assembled on electrode surfaces, were found to be catalytically active towards electrooxidation of CO and MeOH upon activation. The activation involved partial removal of the encapsulating thiolates and the formation of surface oxygenated species. A polymeric film was also used as a substrate for the assembly of the nanoparticle catalysts. When the polymer matrix was doped with small amounts of Pt, a remarkable catalytic activity was observed. These catalysts were characterized utilizing cyclic voltammetry and atomic force microscopy.