Electrochemical and morphological characterization of poly[(R)-(−)-3-(l-pyrrolyl)propyl-N-(3,5-dinitrobenzoyl)-α-phenylglycinate] films deposited on ITO electrodes

Poly[(R)-(-)-3-(l-pyrrolyl)propyl-N-(3,5-dinitrobenzoyl)-α-phenylglycinate] films were deposited on ITO electrodes using potentiodynamic and galvanostatic methods. Polymerization occurred as a charge dependent process at 1.0 V vs. Ag/Ag+(CH3CN) and was not affected by the presence of nitro groups in the monomer. The surface morphology of the film and its electrochemical properties were studied as a function of deposition charge (Qdep) and deposition method. Film thickness increased in a quasi-linear manner with respect to Qdep within the range 40-80 mC cm2. The galvanostatic method provided easier control of Qdep compared with potentiodynamic deposition, and produced a more adherent film with homogeneous grain geometry. Cyclic voltammetry revealed a well defined redox couple at the anodic region, attributable to polymer p-doping, and a poorly defined redox pair at the cathodic region, attributable to the reduction of the nitro group.