To calculate this , we first extract the charge density, , from the number density profile along the direction, . This is achieved by multiplying atom-resolved number densities by their respective partial charges. The includes charged atoms in water, ions, and charged graphene. The curvature of the electrostatic potential, , is connected to as dictated by Poisson's equation 31 : (8) where and are the vacuum permittivity constant and specific electrolyte permittivity, respectively. We obtain by integrating equation 8 from the bulk layer (the net charge density is zero) to the surface of the charged graphene.