Figure 8

2D peak evolution with number of Raman acquisitions. Behaviour of position and shape of 2D peak of Raman spectra acquired in the same spot of the sample: (a) graphene onto Cu substrate; (b) graphene transferred onto SiO₂ substrate. (Insets: change in position and intensity of the single Lorentzian curves used to fit the 2D peak of the spectra).