The reactivity of reduced graphene depends on solvation

The reactivity of reduced graphene sheets (graphenide), obtained by dissolution of graphite intercalation compounds, in particular KC8, was systemically studied by covalent functionalization with 4-fluorobenzenediazonium tetrafluoroborate and 4-iodoaniline in different solvents (5 pure and 7 solvents with addition of K+ chelating agents). Interestingly, proper solvation of the potassium cations was beneficial to the covalent functionalization, while excessive solvation led to destabilization and flocculation, with decreased reactivity of graphenide. The results were confirmed by scanning Raman spectroscopy (SRS) and x-ray photoelectron spectroscopy (XPS).