An electrochemical study of the incorporation of cobalt macrocyclic complexes into nafion films

Cobalt complexes of the macrocyclic ligand, 2,3,9,10-tetramethyl-1,4, 8,11-tetraazacyclotetradeca-1,3,8,10-tetraene (TIM) and its hydroxy derivatives, were incorporated in Nafion films by electrochemical cycling and by ion exchange in aqueous solution. Cyclic voltammetric studies show that the redox potentials of the Co(TIM) complexes undergo a significant anodic shift when incorporated in the films. Electrochemical studies also indicate that, while the Co(TIM) complexes reside in hydrophilic regions of the Nafion film, the metallated porphine complex, cobalt tetrakis(pentafluorophenyl)porphine, is probably immobilized in hydrophobic regions. The incorporation of the complexes was also followed by electronic absorption spectrophotometry.