In summary, we have used QM/MD simulations to investigate the electrowetting phenomena occurring at the graphene/ electrolyte interface. In line with previous experiments and the Young-Lippmann theory, the simulations indicate that graphene surfaces become more hydrophilic upon charging and that the presence of the ions enhances this effect, reducing the surface tension even further. Contrary to the prediction of the YL theory and as shown by some previous simulations of the contact angle , we observe that electrowetting is an asymmetric phenomenon and that different of wetting occurs at different signs of applied voltage, with negative surfaces being systematically more hydrophobic than positive ones. We observe that the effect of the ionic concentration on the surface wettability is not trivial and that it saturates for concentrations larger than 2 M. Experiments carried out on HOPG confirm our simulation data and are in excellent agreement with the computational predictions. The rationalization of the surface tension results proved to be difficult. Competitive effects such as ion adsorption and hydrogen bond number contribute to the surface tension values. Overall, we notice a correlation between the number of interfacial water-water hydrogen bonds and the hydrophilicity of the surface. Finally, we compare the electrochemical capacitance with that predicted by the Young-Lipmann equation. We found that, while the individual values lay within the simulation uncertainty for two out of the three concentrations investigated here, the trend of the predicted capacitance as a function of ionic concentration is wrong, indicating that the EDL structure (related to the electrochemical capacitance) is not directly correlated with the wettability of the surface and different interfacial mechanisms drive the two phenomena.