Electrochemical synthesis and characterization of formic acid-graphite intercalation compound Original Research Article

A formic acid-graphite intercalation compound (HCOOH-GIC) has been successfully synthesized by an electrochemical process whereby formic acid solution serves as both the electrolyte and the intercalate source. Stage structures of 3, 4 and 5 have been revealed by both X-ray diffraction and Raman spectroscopy. Formation of HCOOH-GIC was achieved by controlling the apparent anodic current density in the range of 5–10 mA cm−2 and the reaction duration for 5 to 10 hours. The synthesized compounds can be exfoliated by rapid heating to a relatively low temperature (~400 °C). Their expansion volume reaches 150 to 300 ml g−1 with the specific surface area of 20 to 50 m2 g−1. Since no sulfur is involved in this process, formic acid-GIC can produce flexible graphite for elevated temperature sealing without any corrosive elements. Electrochemical intercalation of other organic acids into graphite has also been investigated in this work.