Vv. Abalyaeva et On. Efimov, ELECTROCATALYTIC SYNTHESIS OF POLYANILINE ON NONNOBLE METAL-ELECTRODES, Polymers for advanced technologies, 8(8), 1997, pp. 517-524
Electrochemical synthesis (ES) of polyaniline (PAn) at the surface cov
ered by an oxide film is realized at a significantly higher voltage th
an is needed for the formation of a nonoveroxidized polymer. The invol
vement of catalytic amounts of the salts of transition metals in ES of
PAn essentially facilitates the process at Ti, Ta, Pb, Al and stainle
ss steel electrodes. IrCI62- anion was found to be an effective cataly
st. During ES, IrCI62- forms a complex with aniline, where Ir-IY oxidi
zes aniline to a radical cation. The formation of radical cation is a
limiting stage ES PAn. It is realized in a moment in the presence of I
rCI62-, thus providing a significant decrease of the induction period
at a potentiostatic synthesis and the lowering of a working potential
at a galvanostatic synthesis. It is shown that the composition of the
complex includes Ir-III and 2 aniline molecules, which form a paramagn
etic dimer inside a coordination sphere. (C) 1997 by John Wiley & Sons
, Ltd.