2.

Electrodeposition process using a three-electrode electrochemical cell. (a) Schematic of the experimental setup for gating graphene and performing cyclic voltammetry. The setup consists of an Ag/AgCl counter electrode, a reference electrode and a graphene working electrode, forming a three-electrode electrochemical cell. Graphene resistance is monitored by applying a drain current of 100 nA at 30 Hz. V_G is the gate voltage, and V_D is the drain voltage. (b) Cyclic voltammogram and (c) graphene gating effect plotted against the gate potential (graphene potential vs reference electrode). Red and blue arrows indicate the direction of the potential sweep. Asterisks in (b) mark the oxidation and reduction peaks. The shaded yellow region highlights the reduction reaction of dissolved air in the solution at the graphene surface.