Optimizing Surface-Enhanced Raman Scattering-Active Au Nanostructures Coated on Indium-Doped Tin Oxide Glass by Combining Chemical Assembly and Electrodeposition Methods

A combined strategy of chemical assembly and electrodeposition methods was used to prepare Au nanostructures as highly efficient surface-enhanced Raman scattering (SERS) substrates. Small Au colloids (3-5 nm) were firstly anchored on the amine-terminated indium-doped tin oxide (ITO) glass, followed by the electrodeposited growth of Au nanoparticles (NPs) using constant potential electrolysis. We systematically investigated the effect of deposition potentials and electrodeposited times on the morphology of Au nanostructures and their coupling states on the ITO glass. The isolated (unconnected) dense-packing Au nanostructure demonstrated highly efficient SERS signals of o-chlorothiophenol when compared to those of aggregated (connected) dense-packing Au nanostructure. SERS enhancement factor of isolated dense-packing Au nanostructure was calculated to be tenth order of magnitude higher than that of aggregated dense-packing Au nanostructure. (C) 2013 The Japan Society of Applied Physics