Thymine adsorption on Ag: pH influence as probed by SERS itle

Authors

  • Hilton B. Aguiar Departamento de Física, Universidade Federal de Sergipe
  • Paola Corio Instituto de Química, Universidade de São Paulo
  • Antônio C. de Sant’Anna Instituto de Química, Universidade de São Paulo
  • Márcia L. A. Temperini Instituto de Química, Universidade de São Paulo
  • Francisco C Nart Instituto de Química de São Carlos, Universidade de São Paulo
  • Frederico G.C. Cunha Departamento de Física, Universidade Federal de Sergipe

Keywords:

Adsorption, Thymine, SERS.

Abstract

The study of the adsorption of organic molecules on metallic surfaces has received attention in the lastyears. This interest is partly due to the goal of constructing nanostructures where the molecular spackingstructure is carefully controlled.  The study of Thymine (5-methyl uracil – 5MU) was performed throughthe use of Surface Enhanced Raman Spectroscopy (SERS) at several pHs and with surface potentialmodulation.  The spectra analysis indicated that the H+ concentration in the solution induces aprotonation/deprotonation equilibrium controlling therefore the molecular orientation on the surface. Twokinds of spectra were obtained for an acidic medium.  At more negative potentials the protonated form ofthe molecule is adsorbed though one of the Oxygen atoms whereas at more positive potentials, thedeprotonated form of the molecule tilts upward and adsorbs though one of the Nitrogen atoms.  In neutralsolutions the molecule is constantly deprotonated and it is verified that the SER spectra does not changewith surface potential

Published

2011-11-19

How to Cite

Aguiar, H. B., Corio, P., de Sant’Anna, A. C., Temperini, M. L. A., Nart, F. C., & Cunha, F. G. (2011). Thymine adsorption on Ag: pH influence as probed by SERS itle. Scientia Plena, 1(1). Retrieved from https://scientiaplena.org.br/sp/article/view/560