Ion modulated electroactivity in thin-film polymers derived from bipyridyl and phenanthroline complexes of iron

摘要: Abstract : Profound changes in the metal-centered electroactivity of thin-film redox polymer/electrolyte systems accompany replacement a conventional electrolyte solution (aqueous tetraethylammonium perchlorate) by any several aq. CH3(CH2)SO3-Na(+) solutions. For example for poly-Fe(4-methyl-4'-vinyl-2, 2'-bipyridine)3m+ film contact with an sodium decanesulfonate solution: (a) overall capacity decreases roughly half order magnitude, (b) rate hopping-based electron transport during charging 20-fold, and (c) thermodynamic potential metallopolymer oxidation moves to significantly less positive value, comparison films equilibrated Further experiments show that modulation behavior is associated uptake release charge-compensating anions reduction (i.e. cations are excluded), degree increases increasing counter anion size, phenomenon chemically reversible. These unusual effects tentatively attributed polymer-based steric constraints on large alkanesulfonate ion incorporation, together hydrophobic partitioning effects. factors apparently conspire couple film-based motion strongly counter- motion. Finally, spectroelectrochemical measurements CH3(CH2) 9SO3-containing-films reversibly confined predominantly mixed-valent form (Fe(II)+Fe(III)), even at electrochemical potentials removed from formal processes film.