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

High Resolution Image Download MS PowerPoint Slide 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.