Preliminary Research on the Liquid Phase Oxidation of Natural Graphite Flakes and Activated Carbon

Based on the Hummers method, graphite oxide and oxidation activated carbon were prepared from graphite and activated carbon. The differences in the structure and property of graphite and activated carbon before and after the liquid-phase oxidation were analyzed. The analysis showed that there were surface oxidation and internal oxidation for natural graphite flakes, but there was only surface oxidation for activated carbon of coconut shells. Surface oxidation took place because the natural graphite flakes and activated carbon possessed many polarity groups, which gave them strong polar and chemical activity. Internal oxidation increased the distance between the layers of graphite flakes from 0.335 4 nm to 0.898 1 nm, which was induced by the polarity groups and H2O between the layers of graphite flakes. In alkaline solution, graphite oxide delaminated into needle-like and spherical nano-particles, some of which coalesced. The oxidation activated carbon was in the form of spherical nano-particles, which coalesced into chain structure.