Electrolysis of Water in the Diffusion Layer: First‐Principles Molecular Dynamics Simulation

Abstract

With Car-Parrinello molecular dynamics simulations the elementary reaction steps of the electrolysis of bulk water are investigated. To simulate the reactions occurring near the anode and near the cathode, electrons are removed or added, respectively. The study focuses on the reactions in pure water. Effects depending on a particular electrode surface or a particular electrolyte are ignored. Under anodic conditions, the reaction continues till molecular oxygen is formed, under cathodic conditions the formation of molecular hydrogen is observed. In addition the formation of hydrogen peroxide is observed as an intermediate of the anodic reaction. The simulations demonstrate that the electrochemistry of oxygen formation without direct electrode contact can be explained by radical reactions in a solvent. These reactions may involve the intermediate formation of ions. The hydrogen formation is governed by rapid proton transfers between water molecules.

Ab‐Initio Molecular Dynamics Simulation of the Electrolysis of Waste Water

“…In the present work I use exclusively Car‐Parrinello molecular dynamics as it is stable and way less costly than BOMD. The study is a continuation of our work on the electrolysis of pure water which was simulated using BLYP without a dispersion correction . In any case we do not make assumptions about the reaction path ways or products.…”

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Classical Motion of the Nuclei in a Molecule: A Concept Without Alternatives

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