Minimizing Electrolyte Velocity in Membraneless Flow-Through Water Electrolysis: Influence of Electrode Geometry Parameters

Abstract

Membraneless electrolyzers make it possible to produce hydrogen without using expensive membranes that can wear out over time. In this study, a transparent alkaline cell was built to study how the structure of the electrode affects gas removal. By directly observing bubble formation, we identified the critical electrolyte velocity, which is the lowest flow rate needed to prevent gas from building up between the electrodes. Fibrous felt electrodes showed the most stable performance, allowing smooth flow and efficient gas transport at low liquid speeds. When the pore size was reduced below 10 micrometers, the required velocity for stable operation became smaller. These results show that adjusting the electrode structure can improve gas separation and make hydrogen production more efficient and affordable.