DISPERSION OF CRYSTALLITES OF THE METAL-SUBSTRATE DURING THE ELECTROPOLYMERIZATION OF 2-HYDROXY-3-AMINOPHENAZINE (HAPH) ON AU - EFFECT OF AU CRYSTALLITES ON THE KINETICS AND MECHANISM OF CHARGE-TRANSFER REACTIONS BETWEEN THE POLYMER AND REDOX SPECIES IN ELECTROLYTE

The electrochemical polymerization of 2-hydroxy-3-aminophenazine (HAPh ) has been studied in aqueous perchloric acid solutions. Under potenti al cycling the polymerization reaction is accompanied by electrodissol ution/electrodeposition of the An substrate onto which the polymer is deposited. TEM observations have revealed two kinds of crystalline gra ins in the pHAPh polymer film. The first kind consists of spherical gr ains of pure gold which are randomly oriented in the polymer matrix. T he second kind consists of oriented well-shaped crystals of unknown co mposition, but most probably crystals of an intermediate Au(III) compl ex. The dispersed Au crystallites affect the kinetics and mechanism of charge-transfer reactions between the polymer and redox species in el ectrolyte, such as dihydroxybenzenes and hydrazine, as well as their p ermeability and incorporation into the polymer film.