Phenothiazine Redox Active Conducting Polymer Films at Nanocomposite Surfaces

A redox active polymer based on phenothiazine (thionine) doped poly (3,4-ethylenedioxythiophene) PEDOT film was examined on a range of transducers (glassy carbon, Pt and screen printed electrodes). This was followed by investigations into the use of super activated carbon (SAC) and platinized super activated carbon (SAC-Pt) nanostructured electrode modifiers for enhanced polythionine/PEDOT film deposition. The Polythionine/PEDOT film was found to undergo a two-electron, two-proton (pH 1-4) or a two-electron, one-proton process (pH 4-8). Electrochemical investigations included scan rate studies confirming the surface confined behavior, with the most stable films (15% decrease in electroactivity) being evident at SPE modified with SAC-Pt - surface coverage (Γ) 1.16 10^-10 mol cm^-2. Surface morphology of the formed film was investigated via SEM/EDX and film hydrophobicity examined via contact angle measurements.