Synthesis and characterization of graphene and functionalized graphene via chemical and thermal treatment methods

Graphene oxide was successfully synthesized via oxidation of graphite, functionalized with dodecyl amine and then chemically reduced using hydrazine hydrate. The graphene oxide was also thermally reduced and exfoliated to obtain graphene. Different characterization methods including elemental, FTIR, XPS, Raman, TGA and XRD analyses were employed to deeply analyze the structure of the resulting materials. The results of different analyses mostly supported each other and demonstrated that different oxygen containing functional groups, those which were capable of grafting to dodecyl amine chains, have been created on the surface of graphite during the oxidation process at the expense of increased defects. Chemical reduction using hydrazine hydrate led to a low extent of oxygenic groups and defects as well as increased graphitization. It was also shown that dodecyl amine plays the role of a reduction agent during the functionalization process. Thermal treatment of graphene oxide resulted in a graphene structure. Structural alterations of different synthesized and functionalized materials were well reflected in their amphiphilic characteristics and morphological features, evaluated using contact angle experiments and SEM analysis, respectively.