Reversible Restoration of Superhydrophobicity in Fluoroalkylsilyl-Grafted Graphene via C–F-Containing Solvents for Anticorrosion and Self-Cleaning Coatings

Hydrophobic coatings are critical for anticorrosion and self-cleaning applications, but many suffer from hydrophobicity decay due to the loss of surface features.In this study, we demonstrate a versatile and rapid method for fully restoring the hydrophobicity of fluoroalkylsilyl-grafted graphene oxide (FGO).This process transforms FGO from a mechanically flattened state (water contact angle (WCA) 120) to a superhydrophobic state (WCA of 152) using C-F-containing solvents.Notably, only C-F-containing solvents, such as 1,1,2-trichloro-1,2,2-trifluoroethane (F113), enabled superior hydrophobicity after restoration.Our findings confirm that this restoration is driven by fluorine-fluorine (F-F) interactions between C-F moieties, which facilitate the reconstruction of surface wrinkling features.Computational studies elucidate the synergistic factors influencing the arrangement of fluoroalkyl silyl (FA) groups on the substrate, including F-F interactions, FA grafting density, and molecular repulsion forces.These factors induce the rotation of critical C-O-Si-C dihedral angles, which reorient the molecular structures relative to the graphene surface.F113 penetrates the interstitial spaces between FA molecules, restoring the bent structures of FGO by leveraging existing F-F interactions, effectively resetting the surface to its superhydrophobic state.These findings offer valuable insights for designing carbon-based materials with a restorable hydrophobicity for anticorrosion coatings and self-cleaning surfaces.