Surface-enhanced Raman scattering, SERS, studies of pyrazine adsorbed on polycrystalline and single crystal electrodes

Abstract

The nature and the orientation of molecules adsorbed on certain rough metallic surfaces can be readily determined by surface-enhanced Raman scattering (SERS). This surface-enhancement phenomenon, allied to basic characteristics of Raman scattering, suggests that the SERS effect is potentially a powerful tool for the investigation of electrochemical problems. However, the magnitude of the enhancement depends on several factors, such as electrode potential, laser wavelength, surface coverage and morphology. The objective of this thesis was to extend the knowledge of the influence of these factors on the overall SERS. Pyrazine (pz) was chosen as the probe molecule. Pz has a molecular centre of inversion which makes this molecule a good model for molecular orientation studies.