H₂ bubble motion reversals during water electrolysis

The dynamics of hydrogen bubbles produced by water electrolysis in an acidic electrolyte is studied using electrochemical and optical methods. A defined cyclic modulation the electric potential applied at a microelectrode to produce pairs interacting H $_2$ controlled manner. Three scenarios interactions are identified systematically. most prominent one consists sudden reversal motion first detached bubble, its return electrode, finally coalescence with second bubble. Attested Toepler's schlieren technique, explanation contactless provided competition between buoyancy thermocapillary effects.