Electrochemical study of polypyrrole/PW_(12)O_(40)~(3-) coatings on carbon steel electrodes as protection against corrosion in chloride aqueous solutions

摘要

Hybrid material polypyrrole/PW_(12)O_(40)~(3-) was electrosynthesised on carbon steel electrodes in acetonitrile medium. Passivation pretreatment of carbon steel in acetonitrile/perchlorate medium was used to avoid electrodissolution of electrode during the polymerisation. These hybrid coatings were evaluated against corrosion in chloride-containing 0.05 M NaOH and solutions obtained by filtering Portland cement slurries. Cyclic voltammetry, polarisation resistance (R_p), and Fe~(2+) concentrations measurements showed that the obtained coatings provide good protection against corrosion in chloride-containing media.