Facile fabrication of hydrophobic alkylamine intercalated graphene oxide as absorbent for highly effective oil-water separation

A facile approach was demonstrated for fabricating hydrophobic alkylamine-functionalized graphene oxide (GO) films as sorbents for cleaning up oil-water mixtures. The hydrophobic alkylamine-functionalized GO (C_n-FGO) sorbents were synthesized using GO and three different alkylamines (hexylamine, dodecylamine, and hexadecylamine) via nucleophilic substitution and amidation reactions. The resulting materials were characterized, and their surface morphologies were also examined. The water contact angles (WCA) were determined to assess the switch in the wettability property of the fabricated sorbents. The pristine somewhat smooth microstructures of the GO sheets became rough with alkylamines intercalation. The WCA of the best performing hexadecylamine-functionalized GO (C₁₆-FGO) surface reached 141.08 ± 1.65°, thus showing excellent hydrophobicity. Moreover, the C₁₆-FGO displayed excellent performance in oil absorption and outstanding efficiency in the separation of the oil-water mixture. The reusability of the fabricated sorbent was assessed to underscore its applicability in more complex scenarios.