Effect of Lorentz force on hydrogen production in water electrolysis employing multielectrodes

The aim of this study was to investigate high-efficiency hydrogen production through water electrolysis by using multiple electrodes; the investigated approach can be applied in industry. In this study, three groups of parallel electrodes were used to conduct experiments and research related to water electrolysis parameters. During electrolysis, we introduced Lorentz forces to an electrolytic cell to determine whether the multielectrode mode is identical to the single-electrode mode regarding increases in hydrogen production. The results showed that a multielectrode group instantly increased gas production. In addition, introducing an external upward magnetic field into an electrolytic cell increased gas production at various concentrations during electrolysis. A downward magnetic field increased gas production in a 10-wt.% KOH electrolyte; this phenomenon does not occur in single-electrode electrolysis. According to IV curves, the decomposition voltage of the electrodes was between 1.87 and 1.93 V. A high-speed camera was used to photograph the magnetic flow field, gas-bubble-layer thickness, and the rising speed of the gas bubbles with and without a Lorentz force. An upward Lorentz force (FL(up)) improved all electrolysis effects, increased the gas bubble layer thickness, and increased the rising speed of the gas bubbles. The current difference increased to a maximum of approximately 370 mA/cm2 when an electrode spacing of 5 mm and a 10-wt.% KOH electrolyte were used. Applying an FL(up), a KOH electrolyte concentration of 20 wt.%, and an electrode spacing of 3 mm increased the hydrogen gas yield by between 2.4% and 4%, according to the amount of accumulated gas measured using gas mass flow.