Electrochemical and electron spectroscopic investigations of iron surfaces modified with thiols

Abstract
In order to develop new composite materials between reactive metals and polymers, it is proposed to place organic monomers at the metal/polymer phase boundary, which can be coupled by covalent/ionic bonds to reactive centres of the metal substrate and later by covalent bonds to the polymer itself. As a first step, the model system iron/n‐decanethiol (n‐decylmercaptan, C10H21SH) has been investigated by AES and XPS. It is shown that the mercaptan binds to metallic clean iron surfaces through the sulphur atom, probably by cleavage of the SH bond. The S 2p3/2 peak has a binding energy of 162.4 ± 0.2 eV. Anodic polarization and ageing in the laboratory atmosphere do not oxidize these chemisorbed molecules; the oxidation reactions of the substrate are suppressed too. After cyclovoltammetry (−1.0 VSHEU ⩽ + 0.6 VSHE), better oriented chemisorbed molecules are packed more densely on top of the surface.