Large-scale, green, and high-efficiency exfoliation and noncovalent functionalization of fluorinated graphene by ionic liquid crystal

In this study, green and high-efficient ionic liquids crystal (ILC)-assisted hydrothermal exfoliation method was developed for exfoliation and functionalization of fluorinated graphene (FG). The proposed method was efficient for exfoliating FG from bulk fluorinated graphite (FGi) at yield reaching 48%. Meanwhile, the reliable interaction between FG and ILC led to noncovalent functionalization of exfoliated nanosheets, where exfoliated FG suspensions were highly stable at room temperature for more than three months without formation of agglomerates. The tribological properties of exfoliated FG nanosheets were then tested as lubricating additive and showed significant decrease in friction coefficient by 82% when compared to pure water. On the other hand, well-dispersed homogeneous FG/-poly (vinyl alcohol) (PVA) composite film with robust mechanical properties and photothermal effects were fabricated thanks to the excellent dispersibility of the FG nanosheets.