ELECTROCHEMICAL STUDY OF POLYANILINE DEPOSITED ON A TITANIUM SURFACE

The electrochemical synthesis of polyaniline on a titanium surface in aqueous sulfuric acid solutions with various concentrations of added a niline has been investigated by cyclic voltammetry. By utilizing a mor e cathodic potential range (up to -0.6 V) for the cyclization than is usual (up to -0.2 V) on Pt and Au electrodes, the new voltammetric wav es have been deconvoluted from the already well-known ones for polyani line. By simultaneous electrochemical and in situ Raman spectroscopic measurements. the Raman bands of polyaniline electrodeposited on a Ti electrode, were assigned for potentials of -0.15 V and -0.6 V. It was found that the new monitored waves were closely related to the so-call ed ''middle'' peaks and appear only when the polyaniline reaches an ov eroxidized state.