Study of the adsorption and electrochemical reduction of lucigenin on Ag electrodes by surface-enhanced Raman spectroscopy

The adsorption and electrochemical reduction of the acridine derivative lucigenin is analysed in this work by surface-enhanced Raman spectroscopy on Ag surfaces. The effect of different anions (chloride and sulphate) on the adsorption mechanism and electrodynamic properties of this molecule were also checked at different excitation wavelengths, and applied potentials. From the surface-enhanced Raman scattering results we have proposed a model of the adsorption mechanism of the different species adsorbed on the Ag electrode. A comparison with the adsorption on Ag colloid is also made. Furthermore, we have studied the charge-transfer between the neutral lucigenin and the metal electrode by analysing the different enhancements of selected bands at different potentials. (C) 2003 Elsevier B.V. All rights reserved.