Table 1.

Conditions of graphite oxide preparation.

Symbol	Condition of Preparation
Method A	graphite (1 g); H2SO4 (30 mL); NaNO3 (3 g); KMnO4 (3 g); 2 h
Method B	graphite (1 g); H2SO4 (45 mL); H3PO4 (5 mL); KNO3 (1.5 g); KMnO4 (5 g); 5 h