Figure 4
From: Opening and reversible control of a wide energy gap in uniform monolayer graphene
Reversible control between the wide-energy-gapped graphene and the pristine graphene by repeated adsorption of sodium and oxygen.
(a) ARPES intensity map of pristine monolayer graphene. ARPES intensity maps measured after the first (b), second (d) and third (f) sodium depositions, where sodium was deposited to saturation coverage. The ARPES intensity maps were measured after the first (c), second (e) and third (g) oxidation, where oxygen was exposed until oxidation was saturated.
