Electrochemical impedance spectroscopy evaluation on the anticorrosive performance of epoxy/polyaniline –ZnO nanocomposite coated mild steel under cathodic polarization

Polyaniline and polyaniline- ZnO nanocomposite were synthesized via in-situ polymerization method. The morphology of the synthesized nanocomposite was determined using of scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy. The influence of nanosized ZnO particles on the corrosion protection of epoxy- PANI (EP/ PANI) coatings on mild steel substrate were investigated by electrochemical impedance spectroscopy (EIS), in 3.5 wt.% NaCl at 65˚C under different cathodic potentials (-0.5, -1 and -1.5 V). The results showed that corrosion resistance, adhesion and cathodic disbonding resistance of EP/PANI in the presence of ZnO increased under cathodic polarization and applying negative voltages.