Corrosion Protection Of Zinc By A Silane Conversion Coating Modified With Graphene Oxide

Graphene possesses an adverse side effect that can aggravate metal corrosion, which impedes its applications in metal protection. This work aims to demonstrate a strategy to effectively inhibit the corrosion activity of graphene and, thus, apply graphene protection to a metal. A gamma-(2,3-glycidoxypropyl)propyltrimethoxysilane/reduced graphene oxide (GPTMS/rGO) composite coating was prepared on a Zn surface by immersion in a GPTMS-modified graphene oxide (GO) solution. The formation mechanism of the coating was investigated by means of scanning electron microscopy (SEM), Raman spectroscopy, Fourier transform infrared absorption (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Afterward, the corrosion resistance of the coating was studied by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP). The results show that a dense layer of the GPTMS/rGO coating covers the Zn surface during the immersion process with the GO reduction reaction. The thickness of the GPTMS/rGO composite coating is approximately 20 mu m, which is much thicker than that of a GPTMS coating. Furthermore, the formed coating shows good corrosion resistance with an i(corr) value of 0.029 mu A/cm(2), and the protection efficiency of the coating reaches 99.94%. After a 12-day immersion in a 0.6-M NaCl solution, the coating maintains its high corrosion resistance.