The FTIR spectra of graphite and XGO are presented in Figures 3(a) and 3(b), respectively.
The graphs show the stretching of hydroxyl group at 3450cm−1, the C=O carbonyl stretching at 1728 cm−1, and the
C–Oepoxide group stretching at 1229 and 1061 cm−1 [12].
The high intensity of the main peaks in XGO confirms the presence of a large amount of oxygen functional groups after the oxidation process.
The peak at 1627 cm−1 is related to the vibrations of adsorbed water molecules.
After the XGO was reduced, hydroxyl and alkoxy groups were significantly decreased (Figure 3(c)), and the phenol C=C ring stretching at 1585 cm−1 was present [10].
In order to effectively eliminate oxygen functional groups on carbon planes, however, strongly acidic environment might be required [5].