The Effect of the Spatial Structure of Electrosynthesized Polyporphyrins on the Catalytic Activity in the Oxygen Electroreduction Reaction

The effect of the number of amino groups in the porphyrin molecule on the catalytic activity of polyporphyrin films was investigated.Polymerization of porphyrins was carried out by electrochemical method.Amino-substituted tetraphenylporphyrins -5-(4-aminophenyl)-10,15,20-triphenylporphyrin, 5,15-di(4-aminophenyl)-10,20-diphenylporphyrin, 5,10,15-tri(4-aminophenyl)-20-phenylporphyrin and 5,10,15,20-tetrakis(4-aminophenyl)porphyrin were used as monomers.Chemical composition of the obtained polyporphyrins was determined by spectral methods.Differences in the chemical structure of the porphyrin monomers lead to the formation of polymers with different spatial organization.Cross-linked polyporphyrins have a more developed surface and greater catalytic activity in the oxygen electroreduction reaction compared to porphyrins with a linear structure.It was found that poly-5,10,15,20tetrakis(4-aminophenyl)porphyrin, which has the most developed porous surface, exhibited the highest catalytic activity.