Diffusion-drift model of ion migration over interstitial sites of a two-dimensional lattice

Abstract

An analytical and numerical modeling of the process of obtaining hydroxyl radicals OH⁰ and atomic hydrogen H⁰ from water molecules on a square lattice based on electrical neutralization of ions OH⁻ on an anode and ions H⁺ on a cathode is conducted. The numerical solution of a system of equations describing a stationary migration of ions H⁺ and OH⁻ over the interstitial sites of a square lattice located in an external electric field is considered. The ions H⁺ and OH⁻ in the interstitial sites of a square lattice are generated as a result of dissociation of a water molecule under the action of external electromagnetic radiation and external constant (stationary) electric field. It is assumed that anode and cathode are unlimited ion sinks. The problem is solved using the finite difference approximation for the initial system of differential equations with the construction of an iterative process due to the nonlinearity of the constituent equations. It is shown by using calculation that the dependence of the ion current on a difference of electric potentials between anode and cathode is sublinear.