Adsorption of phenylacetylene on gold nanoparticle surfaces investigated by surface-enhanced Raman scattering

The adsorption of phenylacetylene (PA) on gold nanoparticle surfaces was investigated by means of surface-enhanced Raman scattering (SERS). The aggregation behaviors were examined by UV-visible absorption spectroscopy and transmission electron microscopy. The phenyl ring of PA appeared to assume a perpendicular orientation with respect to the gold surface from the presence of the v(CH) band at similar to3060 cm(-1). Neither a substantial red shift nor a significant band broadening of the ring breathing modes implied that a direct ring pi-orbital interaction from the phenyl ring with gold substrates should be low. The SERS spectrum of PA on Au surfaces was analyzed by determining the relative enhancement factor of each vibrational band. The multiple peaks in the nu(Cequivalent toC) stretching region were found to vary in the presence of other ionic species. Copyright (C) 2004 John Wiley Sons, Ltd.