Promotion of the active/barrier protection function of epoxy ester coating/steel system utilizing differently synthesized hybrid pigment through zinc acetylacetonate tailored with green inhibitor molecules

This study aims at one-pot synthesis of a series of hybrid anti-corrosive pigments based on zinc acetylacetonate and Urtica Dioica leaves extract at different pHs for inclusion into an epoxy ester (EE) coating and improvement of the coating dual active/barrier anti-corrosion performance. The characterization of the synthesized pigments was accomplished by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses. The modified and neat EE coatings performance was evaluated by electrochemical impedance spectroscopy (EIS) and neutral salt spray (NSS) test. The coating phase investigation by EIS proved the effectiveness of the pigmentation in corrosion protection activity improvement. A magnificent inhibition efficiency (IE%) of about 99.995% was achieved after 70 days of immersion in the pigmented EE coated samples. The pigment particles, which were used in the coating formulation, revealed the most effective function in the solution phase study where an inhibition efficiency of approximately 96% was achieved.