Cu 5,10,15,20-Tetrakis(3-aminophenyl)porphyrin Films Obtained via Polymerization Using Electrooxidation or Superoxide Assistance as Initiating Step

It was shown that the electropolymerization of Cu 5,10,15,20-tetrakis(3-aminophenyl)porphyrin from dimethyl sulfoxide can be carried out both by electrochemical oxidation of the porphyrin, and via initiating the process with electrochemically synthesized superoxide. In oxygenated solutions, initiation of polymerization by superoxide provides a greater contribution to a film formation than electrochemical oxidation of porphyrin. The rates of the film formation by these two mechanisms differ by approximately three times. Despite the differences in the rate of formation and surface morphology of the films for oxygen-free and oxygen-saturated solutions, the resulting materials' surface is formed by particles of similar lateral sizes. The resulting roughness also differs insignificantly. This indicates a proportional increase in both the rate of nucleation and the rate of new phase growth in the presence of oxygen. The long-wavelength absorption edge of the semiconductor material is revealed in the short-wavelength region of the UV-Vis film spectrum. The calculation resulted in the band gap values of 3.48 and 3.19 eV for materials obtained by porphyrin oxidation and via the superoxide assistance, respectively. The influence of the obtaining method of the Cu 5,10,15,20-tetrakis(3-aminophenyl)porphyrin-based material on the reaction of the electro-reduction of oxygen on its surface in an alkaline medium was shown.