Synthesis of polyaniline /CeO2 nanocomposites as inhibitor coating on zinc: Evaluation of the corrosion behaviour

Abstract

In this study, Polyaniline/ceria nanoparticles (PANI/CeO2) nanocomposite (NPs) were prepared by in situ polymerization of aniline in the presence of CeO2 NPs . Ceria nanoparticles were produced via the precipitation of cerium Ce(NO3)3.6H2O in water where the average hydrodynamic diameter of the obtained nanoparticles was about 8 nm (determined by nanosizer) . Infrared spectroscopy “FTIR” and white light interferometry analysis were used to characterize the obtained PANI/CeO2 and also the electrodeposited coatings. To overcome the low solubility of the polymer /ceria nanoparticles, the composites was dissolved in dimethyl sulfoxide solvent under ultrasonic stirring. The electrochemical behavior of zinc substrate in the corrosive medium with and without PANI / CeO2 addition was studied using d.c polarization techniques and electrochemical impedance spectroscopy “EIS”. All the obtained results have shown the good behavior of PANI/CeO2 in the protection of zinc against corrosion. Indeed, the addition of 66 ppm of PANI / CeO2 to the aggressive solution 0.5N NaCl provides to the substrate an electrochemical efficiency about of 77.74%. It has been shown that PANI /CeO2 acts on the anodic process. the hybrid PANI/ CeO2 NPs can be considred as an intersting way to enhance the protection performance of the PANI/CeO2 on zinc