Water nanoelectrolysis: A simple model

A simple model of water nanoelectrolysis—defined as the nanolocalization at a single point of any electrolysis phenomenon—is presented. It is based on the electron tunneling assisted by the electric field through the thin film of water molecules (∼0.3 nm thick) at the surface of a tip-shaped nanoelectrode (micrometric to nanometric curvature radius at the apex). By applying, e.g., an electric potential V 1 during a finite time t 1, and then the potential −V 1 during the same time t 1, we show that there are three distinct regions in the plane (t 1, V 1): one for the nanolocalization (at the apex of the nanoelectrode) of the electrolysis oxidation reaction, the second one for the nanolocalization of the reduction reaction, and the third one for the nanolocalization of the production of bubbles. These parameters t 1 and V 1 completely control the time at which the electrolysis reaction (of oxidation or reduction) begins, the duration of this reaction, the electrolysis current intensity (i.e., the tunneling current), the number of produced O2 or H2 molecules, and the radius of the nanolocalized bubbles. The model is in good agreement with our experiments.