Raman spectroscopy has been accepte

Raman spectroscopy has been accepted to be a powerful and nondestructive tool to characterize the quality of graphitic materials. The significant structural changesresulting from the solvothermal reaction process from GO to rGO were also reflected in the Raman spectra.
Figure 3 (spectra a and b) shows the Raman measurements of graphite before and after the modified Hummers' method. There were two characteristic peaks in the spectrum of graphite: the D (disordered) peak centered at 1,347 cm−1 and the G (graphitic) peak at 1,582 cm−1.
The D band is attributed to the disruption of the symmetrical hexagonal graphitic lattice as a result of edge defects, internal structural defects, and dangling bonds.