Tetrakis porphyrin electrochemical polymerization

Electrochemical polymerization offers particular advantages in that polymerized porphyrins can form electroactive, adherent and stable films on solid electrodes. Oxidative electropolymerization of several porphyrins and metalloporphyrins have been reported . Special focus has been placed on amino-substituted porphyrins due to the propensity of aniline to form electroactive polymers. Murray et al. reported on the electropolymerization of tetrakis(o-aminophenyl)porphyrin and several para-, ortho-, and meta-substituted tetrakis(aminophenyl)porphyrins with Co as a central metal s. They found that poly-Co(o-NH2)TPP films are effective catalysts for the electroreduction of oxygen in aqueous solution. Metalloporphyrin films on solid electrodes have been mainly characterized by voltammetry and resonsance Raman spectroscopy. The electrochemistry of ruthenium paradiethylamino substituted tetraphenylporphyrins recently have been investigated . This study reports the ac impedance and UV-visible reflectance spectroscopic studies of paradiethylamino substituted tetra-phenylporphyrin films formed via an oxidative electropolymerization process. 

Figure 1. A continuous scan cyclic voltammogram of nickel(II) tetrakis(3-methoxy-4-hydroxyphenyl)porphyrin [(TMHPP)Ni] indicating film formation (a), reaction pathway for the electrochemical oxidation of MHPP)Ni in basic aqueous media (l-ll) and the reaction leading to polymerization of fully oxidized (TMHPP)Ni (lll-V)...

Mafinski, T., A. Ciszewski, J. Bennett, and J.R. Fish (1991). Characterization of conductive polymeric nickel(II) tetrakis(3-methoxy-4-hydroxy-phenyl)porphyrin as an anodic material for electrocatalysis. J. Electrochem. Soc. 138(7), 2008-2015. 

Ciszewski, A. and G. Milczarek (1996). Electrocatalytic oxidation of alcohols on glassy carbon electrodes electrochemically modified by conductive polymeric nickel(II)tetrakis(3-methoxy-4-hydroxyphenyl)porphyrin film. J. Electroanal. Chem. 413, 137-142. 

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