In the Introduction we have mentioned the work by Claramunt et al., 2015, which is regarding the Raman spectroscopy of GO and rGO (reduced graphene oxide). Claramunt and coworkers remember that Brodie, Staudenmaier, Hummers and Offeman proposed GO "as a carbon compound where oxygen functional groups are attached at carbon atoms within the hexagonal plane". Accordingly, "GO consists of two main regions constituted by hydrophobic π-conjugated C-sp 2 and the C-sp 3 domains. The latter are mainly constituted by alcohol and epoxy groups located at the basal plane and carboxylic acids groups at the structure edges" . The control of oxygen functionalities attached to the carbo-layer is tuning the electronic and mechanical properties of GO, and therefore, GO "is often reduced by chemical agents, or thermal annealing, obtaining reduced graphene oxide (rGO)" , and references therein). For the reduction of GO, hydrazine or vitamin C are used. These agents introduce functional groups with amino nitrogen atoms when hydrazine is used or some O-groups with the reduction by means of vitamin C. "Alternatively, GO of different oxidation grade can be obtained by thermal reduction" (Claramunt et al., 2015, and reference there in).