Electrochemical investigation of the properties of Co doped ZnO nanoparticle as a corrosion inhibitive pigment for modifying corrosion resistance of the epoxy coating

• Corrosion inhibitive pigment based on ZnOCo was synthesized through combustion method.
• Doping ZnO nanoparticle with Co enhanced its inhibition properties considerably.
• ZnOCo nanoparticle could enhance corrosion protective performance of epoxy coating.
• Co doped ZnO nanoparticles behaved as efficient barrier and inhibitive pigment.

Co doped ZnO nanoparticles were synthesized by combustion method. Then, the epoxy nanocomposites were prepared using various amounts of nanoparticles. Salt spray and electrochemical impedance spectroscopy (EIS) were used in order to investigate the corrosion inhibition effects of nanoparticles on the steel substrate. The morphology and composition of the films precipitated on the steel surface were investigated by scanning electron microscope (SEM) and energy dispersive spectroscopy. Results revealed that the corrosion inhibition properties of ZnO nanoparticle were significantly enhanced after doping with Co. Moreover, Co doped ZnO nanoparticles enhanced the corrosion resistance of the epoxy coating effectively.