Angle‐Dependent Bubbly Flow and the Effects on Gas Evolution in Water Electrolysis

ABSTRACT For tight assembly water electrolysis devices, integrated electrodes serve as the catalyst support but also the component for gas diffusion. While bubble management within integrated electrodes has been recognized as a critical performance‐limiting factor at high current densities, due to the lack of a comprehensive understanding of buoyancy and electrode tilt. Here, we propose a synergistic effect between electrode tilt angle and buoyancy forces on hydrogen evolution reaction (HER) bubble detachment kinetics. As inspired by the improved performance as tilting commercial nickel mesh (NM) electrode to 45°, we systematically investigate the angular dependence of bubble dynamics on a Ni‐wire model electrode through high‐speed imaging and electrochemical analysis, and clarify the optimized tilt angle of 45° and the resultant in‐plane bubbly flow field. Based on the findings, the proposed angular‐perforated nickel electrode (APNE) with an open‐structured inclination achieves a current density of 4.38 A cm − 2 at 2 V for anion exchange membrane water electrolysis (AEMWE), outperforming NM by 35% and nickel foam (NF) by 25%, even though the effective reaction area is smaller than that of NF, due to superior bubble detachment behavior. This work demonstrates that strategic electrode angulation can fundamentally alter bubble transport pathways, offering a scalable solution for high‐performance water electrolysis.