Effects of excluded volume on the electrolyte distribution around a charged sphere

A recently developed method is used to calculate the main effects of excluded volume on the distribution of ions around a charged central sphere in thermal equilibrium. The authors find significant corrections to the results of the conventional Gouy-Chapman theory when the electrostatic energy due to the charge of the sphere is large compared with the thermal energy. The concentration shows a distinct saturation effect, while at the surface of the sphere the known saturation of the potential is lifted. Furthermore, the effect of excluded volume is found to be strongly dominated by the excluded volume of ions with a charge opposite to the charge of the sphere.