Synthesis and characterization of a high-quality nanocontainer based on benzimidazole-zinc phosphate (ZP-BIM) tailored graphene oxides; a facile approach to fabricating a smart self-healing anti-corrosion system.

This paper describes the synthesis of a novel corrosion inhibitor nanocarrier based on benzimidazole-zinc phosphate (ZP-BIM) tailored graphene oxide (GO) and its application in the epoxy-based composite coating for the achievement of smart self-healing anti-corrosion properties toward mild steel (MS) against saline solution. The morphology and chemical/phase composition of the GO-ZP-BIM particles were investigated by FE-SEM/EDS, FT-IR, Raman spectroscopy, XPS and XRD methods. The amounts of the released inhibitive ions (i.e. PO43- anions/Zn2+ cations) and BIM molecules from the GO-ZP-BIM particles in the NaCl solution were determined by ICP analysis and UV-Visible method. The electrochemical test results in the solution phase revealed the high inhibition activities for GO-ZP (68.2%) and GO-ZP-BIM (86.5%) composites. The results of the FE-SEM/EDS analyses proved that a compact inhibitive film composed of the zinc and BIM containing compounds generated on the steel surface when subjected to the saline solution containing the GO-ZP-BIM extract. The EIS and salt spray test results demonstrated excellent barrier/active inhibition performance of the epoxy film loaded with 0.15 wt% GO-ZP-BIM particles. The combined barrier effect of the GO sheets and the inhibition activity of ZP-BIM resulted in the superior self-healing anti-corrosion properties for the epoxy film.