Figure 3: Oxygen intercalation underneath graphene.

(a,b) (bottom) C1s and Al2p photoemission spectra acquired at different O2 exposure. (top) C1s and Al2p high-resolution spectra acquired after the formation of a thick alumina nanosheet underneath Gr, the fit components are shown superimposed to the experimental data. (c) Top and side views of the simulated Gr/Al2O3 structure. (d) ARPES measurement of the Gr/Al2O3 electronic band structure along the K–M–K′ direction. (e) DFT calculated energy band dispersion for the Gr/Al2O3 system.