Representative AFM images of the fct-EEM and fct-EEG are shown in Figure and aided the exfoliation process, leading to a thinner flake. The diazonium salts also slightly aided the exfoliation of graphite; the thickness of graphite reduced from ~500 nm (Figure ) to around 100 nm (Figure ). The distribution of the lateral flake size and the thickness of fct-EEM were obtained by measuring the flakes in the AFM images (Figure and Figure ). The thickness of the fct-EEM flakes is around 4 nm. Compared to unfunctionalized EEM (Figure ), fct-EEM has smaller flake sizes (~0.5 μm). The fct-EEG also has more flakes with small sizes than EEG does (Figure ). It is suggested that this is because the functionalization helps with the dispersion of the flakes in IPA and water and thus it is easier to obtain small flakes during the ultra-sonication. The two dominant peaks locating at ~380 cm -1 (E 1 2g) and ~408 cm -1 (A1g) are attributed to the in-plane vibration and out-of-plane lattice expansion . The average peak position of E 1 2g is plotted against A1g as shown in Figure and it was noted that both E 1 2g and A1g are blue-shifted.