Synthesis of Ternary Intercalation Compounds in the Graphite–HNO3–R (R = H2SO4 , H3PO4 , CH3COOH) Systems

The reactions of stage II–IV graphite nitrates with concentrated H2SO4 , H3PO4 , and CH3COOH were studied at graphite : acid weight ratios from 3 : 1 to 1 : 1. The results demonstrate that the reactions in question follow different paths. In the graphite nitrate–H2SO4system, the reaction decreases the stage index and yields a ternary graphite intercalation compound. The contents of intercalated HNO3and H2SO4are controlled by the amount of H2SO4and the stage index of the parent graphite nitrate. The reaction between graphite nitrate and H3PO4leads to partial replacement of HNO3by H3PO4 , increasing the identity period without changes in the stage index. The results for the graphite nitrate–CH3COOH system provide no direct evidence for the formation of an intercalation compound with HNO3and CH3COOH. It is shown that varying the nature and amount of the second intercalate species opens up possibilities for preparing oxidized graphite with controlled physicochemical properties.