Effects of the Dielectric Response of Single-Component Liquids and Liquid Mixtures on Electrochemical Properties between Charged Plates

Abstract

We study the dielectric properties of single-component liquids and liquid mixtures between charged plates and develop a modified Poisson–Boltzmann (PB) equation using Booth’s theory. Our theory accounts for the permanent dipole moment and polarizability of solvents and the hydrogen bonds between solvents. We demonstrate that these key parameters are crucial for capturing the reorientation of solvent dipoles under external electrostatic fields. Our results show that variations in the capacitance of ionic solutions can be nonmonotonic, whereas the conventional PB theory predicts monotonic behavior. Specifically, the effect of hydrogen bonding produces highly nonmonotonic behavior that depends on the surface charge density and applied voltage. The resultant capacitance can be enhanced by hydrogen bonding, but a significant decline in the capacitance can also occur as the applied voltage is increased. Furthermore, our novel finding is that field-induced changes in the dielectric value may cause the unconventi...