Vibrational Spectroscopic Investigation of Benzoic Acid Adsorbed on Silver Academic Article uri icon

abstract

  • The surface-enhanced Raman scattering (SERS) of benzoic acid has been investigated in aqueous silver sol and at a silver electrode. The adsorption behavior of benzoic acid seemed very dependent on the nature of substrate. On the electrode surface, the molecule was found to adsorb preferentially, after deprotonation, via the oxygen lone pair electrons, assuming a perpendicular orientation with respect to the surface. In contrast, the benzoate species appeared more likely to take a flat or tilted orientation on the sol surface. The same observation could be made for 4-methylbenzoic acid. According to the ab initio quantum mechanical calculation which modeled the silver surface as an Ag5+ cluster, the perpendicular orientation appeared to be energetically more favorable than the flat orientation. Although the origin of such a different adsorption mechanism could not be clarified, it was tentatively ascribed to the different surface morphology along with the intrinsic difference in the nature of SERS active sites on the two surfaces. © 1994 American Chemical Society.

altmetric score

  • 3

author list (cited authors)

  • Kwon, Y. J., Son, D. H., Ahn, S. J., Kim, M. S., & Kim, K.

citation count

  • 112

publication date

  • August 1994