show larger values due to the presence of explicit water. Our study showed that the total reorganization energies are strongly influenced by the way water coordinates toward the redox couples (See Fig. ). When molecules are located at the closest distance from the electrode, the strong interaction between the molecules and the out-of-plane vibrations of graphene leads to smaller λ values. As shown in Fig. , the partial insertion of a water molecule between neutral graphene and OH-Vi 0 leads to an increase in the distance and consequently a non-negligible enhancement in λ during the second ET. Compared to the 2HNQ 0/-1 reaction, 2HNQ -1/-2 shows a symmetrical increase in the averaged distance from graphene (about 1.3 Å more). This results in an increase in λ to 1.14 eV.