An X-ray photoelectron spectroscopic study of multilayers of an electroactive ferrocene derivative attached to platinum and gold electrodes

Pretreated (anodized) Pt and Au electrode surfaces derivatized with (1,1:ferrocenediyl)dichlorosilane have been analyzed by X-ray photoelectron spectroscopy (XPES). The derivatized surfaces exhibit Fe 2p3/2 bands with binding energies consistent with ferrocene iron and with large companion satellite peaks. Using a layer model, relative Fe 2p3/2 and electrode substrate intensities (Au or Pt) can be correlated with ferrocene coverage measured by cyclic voltammetry. The results indicate that electrochemical charge transfer can occur through ferrocene/silane layers of thicknesses exceeding 100 Angstrom.