Raman spectroscopy was taken using a Renishaw InVia Raman system (λ = 633 nm). Fourier transform infrared (FTIR, Thermo Electron Corporation, Nicolet 5700) spectroscopy was used to identify the functional groups on EEG and EEA flakes. Transmission Electron Microscopy (TEM, FEI Tecnai G2 20, LaB6) was used to observe bright field images and diffraction patterns of the graphene flakes. X-ray Photoelectron Spectroscopy (XPS) was performed using an ESCA2SR spectrometer (ScientaOmicron GmbH) via monochromated Al Kα radiation (1486.6 eV, 20 mA emission at 300 W, 1 mm spot size) with a base vacuum pressure of ~1 × 10 -9 mbar. Charge neutralisation was achieved using a low energy electron flood source (FS40A, PreVac). Binding energy scale calibration was performed using C-C in the C 1s photoelectron peak at 285 eV. Analysis and curve fitting was performed using Voigtapproximation peaks using CasaXPS .