Synthesis of Graphite Intercalation Compounds

Abstract

The intercalation process involves a chemical reaction between a layered host material and reagent which results in the insertion of new atomic or molecular layers, termed intercalate layers, between the host layers. In graphite, this reaction takes advantage of the weak (van der Waals) bonds between carbon layers. The intralayer hexagonal organization of the carbon atoms is not affected by intercalation. Typical syntheses of graphite intercalation compounds (GICs) take place at moderate temperatures (T< 700°C), and occur on a relatively short time scale (several, minutes to several days). Intercalation reactions are known to occur between graphite and literally hundreds of reagents. The compounds are, for the most part, very unstable in the open laboratory environment, and they must therefore be handled with extreme care and encapsulated in vacuum or in an overpressure of inert gas or reactant. In many cases, the samples are sufficiently unstable to merit in situ investigation of the physical properties.