Photochemical Strategies for the Seed-Mediated Growth of Gold and Gold?Silver Nanoparticles

摘要

Gold nanoparticles (AuNP) can be used as seeds for thensynthesis of larger AuNP of controllable size with narrow size distribution bynphotochemical reduction of additional Au(III) using water-soluble benzoins ornH2O2 as sources of reducing radicals. Further, beyond simply enlarging thenAuNP, it is possible to add a shell of another metal, such as silver, leading tonAu/Ag core−shell structures with controllable dimensions for both core andnshell. This strategy illustrates the fine spatial and temporal control achievablenusing clean photochemical techniques without the addition of hard surfacenligands often necessary to control the size and structure of gold−silvernnanostructures. The mild nature of the surface coverage makes thesennanomaterials ideal for further surface modification.