Improving the polyester powder coating self-healing anti-corrosion properties via the steel surface decoration with Ce-doped-ZIF-8@ZPMn film

This study aimed to investigate the effects of ZPMn coating modification with ZIF-8 (MOF) crystals on the corrosion rate, cathodic disbonding, and adhesion properties of the polyester (Es) coating. Also, in order to increase the self-healing and adhesion capabilities of the coating in saline environments, the Es-ZPMn-MOF was modified by cerium ions (Ce3+). The treated steel's surface has been characterized using FTIR, Raman, and FE-SEM techniques. The barrier capabilities, self-healing properties, and adhesion efficiency of the polyester coating were further analyzed using Salt spray (SS), FE-SEM and EDX/mapping, EIS, Pull-off, and cathodic delamination experiments. According to the EIS results, after 24 h of immersion, the Es-ZPMn-MOF/Ce sample's (in scratched form) corrosion protection properties increased significantly (around 35%). The pull-off outcomes showed that compared to the Es sample, the polyester coating modified by ZPMn-MOF/Ce film had the most significant increase in adhesion strength and the least amount of adhesion loss (around 25%). Moreover, the cathodic delamination experiments showed that using the ZPMn-MOF/Ce film increased the Es's resistance to disbondment by 92%.