Comparative corrosion resistance of graphene sheets with different structures in waterborne epoxy coatings

Although substantial statements report the capability of graphene for corrosion prevention , its further application is limited by the non-comprehension of its structural variation in different coatings. Herein, graphene sheets with four structures were incorporated waterborne epoxy to fabricate different types of composite coatings (named EP-G a , EP-G b , EP-GO and EP-GS, respectively) as well as the pure waterborne epoxy coating was fabricated for comparison. The corrosion behaviors of as-fabricated coatings with and without graphene sheets were systematically characterized via potential, impedance testing and Tafel curves by immersing in 3.5 wt % NaCl solution. It was remarkable to point out that EP-G a composite coating could possess a promising long-term corrosion protection capability. The corrosion protection mechanism of graphene-based composite coatings were verified as the barrier effect of impermeable graphene sheets that confirmed by the analysis of corrosion products. Moreover, the scanning vibrating electrode technique in-depth revealed the relationship between the graphene structures and corrosion performances of the composite coatings. With the occurrence of commercialized application of graphene-based coatings, these works displayed a suitable approach toward the long-term corrosion behavior, which was able to be extended to other two-dimensional materials for anti-corrosion coatings.