Corrosion inhibition of carbon steel by polyaniline nanofibers

Uniform polyaniline (PANI) nanofibers were synthesized by interfacial polymerization. Transmission electron microscopy (TEM) image shows that the nanofibers have average diameter of 30–60 nm and length of 200–400 nm. And the PANI nanofibers have the good dispersion stability in the ethanol. The anti-corrosion performance of PANI nanofibers and aggregated PANI-coated carbon steel samples exposed to 5% NaCl aqueous solution was evaluated by electrochemical corrosion measurements. The results show that the carbon steel coated with PANI nanofibers has more excellent corrosion protection than that with aggregated PANI. Raman spectroscopy analysis indicates that the surface of carbon steel coated with PANI nanofibers formed better passive layer, which is composed of α-Fe2O3 and Fe3O4.