Hg. Hong, KINETIC-BEHAVIOR OF A ROTATING GOLD DISK ELECTRODE MODIFIED WITH A SELF-ASSEMBLED FERROCENECARBOXAMIDOYL MONOLAYER BASED ON ZIRCONIUM PHOSPHONATE, Electrochimica acta, 42(15), 1997, pp. 2319-2326
A rotating gold disk electrode was modified with a ferrocenecarboxamid
oyl monolayer, which is ionically bound to a well-ordered zirconium ph
osphonate film on electrode surface. Voltammetric behaviors on a modif
ied Au disk electrode have been studied in solutions containing electr
oactive species. This electroactive film with constant thickness of ca
. 29 Angstrom simultaneously shows not only an electron-transfer block
ing property but also an electron-transfer mediating property. The lim
iting steady-state current was measured as a function of rotation rate
and overpotential for monomer-mediated oxidation of Fe(CN)(6)(4-) and
was analyzed to get kinetic parameter values (k(et), K-0, and alpha)
by a simulation fitting program. The extracted values of rate constant
for the monomer/redox couple electron-exchange reaction and the irrev
ersible charge transport reaction indicate that a relatively facile el
ectron transfer reaction occurs in the high overpotential region even
though the zirconium phosphonate film makes the electron propagation r
ate through the film slower. (C) 1996 Elsevier Science Ltd.