The electrochemical oxidation of aliphatic amines (primary, secondary, and tertiary) has been investigated by cyclic voltammetry and preparative electrolysis. The oxidation mechanisms have been established, and the lifetimes of the radical cations have been measured for secondary and tertiary amines. These results have been put in parallel with the attachment of amines to glassy carbon, Au, and Pt electrodes by cyclic voltammetry, X-ray photoelectron spectroscopy (XPS), and infrared reflection-absorption spectroscopy (IRRAS). It is then possible to show that it is not the radical cation but the radical obtained after the deprotonation which reacts with the electrode surface. XPS results also point to the existence of a covalent bond between Au or Pt and the organic moiety.

The grafting of 4-nitrophenyl groups on carbon or metallic surfaces without externally applied electrochemical induction is described. Clean surfaces of glassy carbon (GC), copper, nickel, iron, and zinc substrates were dipped in a solution of 4-nitrobenzene diazonium tetrafluoroborate salt in acetonitrile. After the modified surfaces were rinsed, they were analyzed by FT-IRRAS, cyclic voltammetry, XPS, and AFM. The main result of this investigation is the spontaneous formation of a multilayer coating without electrochemical induction regardless of the substrate used. Influence of immersion time and of 4-nitrobenzene diazonium tetrafluoroborate salt concentration on the grafting were also investigated.