Preparation and characterization of sulfur-free exfoliated graphite with large exfoliated volume

Abstract Sulfur-free exfoliated graphite with large exfoliated volume was prepared via chemical oxidation combined with microwave irradiation by using nature flake graphite, perchloric acid and potassium permanganate as raw materials. The influences of some experimental parameters on the exfoliated volume were discussed in detail. It was found that the optimum preparing conditions went as follows: m(nature flake graphite):m(perchloric acid):m(potassium permanganate) = 1:4:0.5, the reaction temperature and time were 35 °C and 40 minutes, respectively. The exfoliated volume of exfoliated graphite which was obtained by microwave irradiation could reach up to 760 ml g− 1. Many network pores existed in the worm-like particles of exfoliated graphite according to scanning electron microscope images.