Potentiometric Analysis of Bubble Dynamics Inside Ni Foam Electrodes During Alkaline Water Electrolysis

In the pursuit of a hydrogen society free from carbon dioxide emissions, water electrolysis using renewable electricity for hydrogen production is attracting attention. Alkaline water electrolysis (AWE) is a low-cost technology for this process. Reducing the energy consumption of AWE requires the effective removal of electrolysis bubbles, which inhibit reactant mass transfer and limit the electrochemical surface area around the electrodes. This study evaluated the performance of Ni foams applied to anodes and cathodes in AWE, considering factors such as electrode structure, flow rate, and operating pressure. Additionally, bubble behavior within the electrode was studied by analyzing potential changes at a constant current density to evaluate its effect on performance. The outcomes from polarization curves analysis and oscillation studies identified the optimal flow rates and pressures for bubble removal.