The ∆A 0 IJ value indicates the direction of a spontaneous electrochemical reaction. It is negative when the reduction reaction, i.e., the ET from graphene to the molecule, is energetically favorable. It appears that only the first ET from doubly negatively charged graphene to the individual DMDQ +2 , OH-Vi +2 , Me-Vi +2 , and 2HNQ 0 molecules are thermodynamically favorable. Clearly, the energy level of the electrode, which is adjustable by the externally applied potential, plays an important role in the interactions between electrode and electrolyte. For example, one can apply a negative potential to shift the parabola of the product downward to favor the ET reactions.