ELECTROOXIDATION OF 1-NAPHTHYLAMINE IN ACIDIC AQUEOUS-MEDIUM - RESPONSE OF THE FILM FORMED OF DIFFERENT ELECTRODE MATERIAL WITH THE PH

Electro-oxidation of 1-naphthylamine (1-NAP) in acidic aqueous media l eads to a film formation of poly-1-naphthylamine (PNAP-1) which strong ly adheres to the surface of the base electrode. Under carefully chose n conditions of formation, i.e. initial and switching potential, waiti ng time at the switching potential and temperature, in the film respon se a second anodic peak (III) with no cathodic counterpart appears at more positive potentials than the I/II peak system already reported. T he conditions that rule the growth of the mentioned peak are reported here. The response of the whole system as a function of pH is studied under the potentiodynamic perturbations as well as under open circuit conditions. Pt, Au and SnO2 were used as starting electrode material f or the PNAP-1 electroformation. It has been found that only on SnO2 th e film can exhibit its own response to pH, while the response of the f ilms grown onto Pt and Au are mostly due to those corresponding to the base electrode.