Self-healing active anticorrosion coatings with polyaniline/cerium nitrate hollow microspheres

Polyaniline (PANI) hollow microspheres have been synthesized by self-assembly method and doped with Poly (2-acrylamido-2-methylpropane sulfonic acid) (PAMPS) and Ce ions. PANI/Ce(NO3)3 hollow microspheres of large specific area (10.9 m2/g) and ultrahigh electrical conductivity (46.8 S/cm) were applied as additives and dispersed in epoxy coating. EIS and Tafel polarization tests indicated that PANI/Ce(NO3)3 coating exhibiting excellent anticorrosion performance. Raman spectra revealed that compact and thin Fe3O4 layer has been formed on steel surface to block aggressive electrolytes. In addition, Ce ions promoted the formation of passivation layer and assured protection against corrosion without toxic inhibitor.