Electrochemical Formation of a Covalent–Ionic\nStage‑1 Graphite Intercalation Compound with Trifluoroacetic\nAcid

Abstract

A pure\nstage-1 graphite intercalation compound (GIC) has been prepared\nby the electrochemical oxidation of graphite in trifluoroacetic acid\n(CF₃COOH). During the CF₃COOH-GIC formation,\ncovalent as well as ionic bonds between the trifluoroacetic acid and\ngraphite layers are formed. Electrochemical reduction of the stage-1\nGIC leads to the deintercalation of ionically bonded intercalate,\nyielding the stage-2 covalent GIC. The interlayer spacing is 8.10\nÅ for stage-1 and 11.62 Å for stage-2 GIC. Further electrochemical\noxidation of stage-1 CF₃COOH-GIC does not lead to the exfoliation\nof the GIC product, and the GIC has relatively high stability in air.