Preparation of expanded graphite by peracetic acid pre-oxidation intercalation expansion method and its effect on electrical conductivity

Abstract:

In this work, the graphite intercalation compounds with different oxidation degrees are prepared via a chemical oxidation method, using the peracetic acid as a preoxidant and the concentrated sulfuric acid as an intercalating agent. Further, expanded graphite is prepared by microwave-heating expansion. SEM, XRD, and FT-IR are used to characterize the morphology, structure, and changes of oxygen-containing functional groups of graphite intercalation compounds and expanded graphite. Furthermore, the effect of pre-oxidation time on the expansion volume and electrical conductivity of expanded graphite is studied. The results show that when the preoxidation time is 20 min, the intercalation expansion is the best, the expansion volume of the obtained expanded graphite reaches 275 mL/g, and the electrical conductivity of the prepared flexible graphite foil reaches 2000 S/m, showing excellent performance. Electrical conductivity. This work provides an idea for the green preparation of expanded graphite with high expansion volume. The results show that the intercalation expansion is the best when the pre-oxidation reaction time is 20 min, and the expansion volume of expanded graphite reaches the maximum of 275 mL/g. Under the optimal expansion effect, the conductivity of the prepared flexible graphite foil reaches 2000 S/m, showing excellent electrical conductivity. This work provides an idea for the green preparation of expanded graphite with high expansion volume.