Evaporation of Water Droplets and Corrosion on Various Graphene Coatings

The wettability, evaporation droplets, and corrosion were experimentally studied for textured copper samples with graphene and smooth copper samples with fluorographene. With increase in the fluorination time, the wettability on fluorographene surfaces grew. Textured graphene surfaces have shown the maximum starting contact angle of 93°. Unlike smooth surfaces with graphene, the textures had a more stable contact line. With the fluorination time increase from 20 to 240 hours, inhomogeneous structures were formed on the surface of fluorographene, which led to roughness increase 2.6–2.7 times. With longer fluorination of graphene, the corrosion current became higher, which is associated with the defectiveness and high hydrophilicity of the surface. With longer fluorination time, the corrosion current became 1.6 times higher. As (EDS) analysis showed, corrosion led to about 10 to 15-fold decrease in the amount of fluorine on fluorographene. The highest anti-corrosion properties were demonstrated by a copper sample subjected to laser texturing, on which several layers of graphene were synthesized.