Fabrication of a highly effective corrosion protection system based on GO- PANI-NE/epoxy nanocomposites

摘要

One effective strategy for corrosion protection of metals is fabrication of coatings with combined barrier and inhibitive characteristics. It has been shown that barrier protection performance of the coatings can be highly improved through addition of graphene oxide (GO) nanosheets. However, the main challenge of this system is poor inhibition properties when there is a slight mechanical damage in the coating. So, in this study the graphene oxide based Nano container filled with corrosion inhibitor was fabricated through layer-by-layer (L-b-L) assembly procedure. For this purpose, the GO sheets were firstly functionalized by polyaniline, and then green corrosion inhibitors obtained from Nettel extract deposited on the GO-PANI sheets. The morphology, microstructure and chemistry of GO, GO-PANI and GO-PANI-NE were characterized by field-emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA) and X-ray diffraction (XRD) analysis. Then, the GO/epoxy, GO-PANI/epoxy and GO-PANI-NE/epoxy nanocomposites were fabricated and their corrosion protection performance was studied by electrochemical impedance spectroscopy (EIS). Results showed that GO-PANI-NE was successfully synthesized by LBL assembly procedure. Data confirmed that inclusion of GO-PANI-NE nanosheets into the epoxy coating significantly unproved its corrosion protection properties. It was shown that both barrier and inhibitive characteristics of the coatings were remarkably improved after addition of the GO-PANI-NE nanosheets.