Advances in bubble dynamics regulation for water electrolysis hydrogen production: From interfacial design to external-field intensification

Gas bubble dynamics at electrode interfaces during water electrolysis significantly impair hydrogen production efficiency through surface coverage, ohmic polarization, and mass transfer limitations, leading to 7–25 % energy losses. This review systematically examines multiscale strategies for bubble regulation, from interfacial design to external-field intensification. We first analyze the three primary mechanisms of bubble-induced overpotential and integrate a force-balance model at gas-liquid-solid interfaces to elucidate critical bubble detachment conditions. Advanced electrode engineering approaches are then discussed, including wettability modulation (superhydrophilic/superaerophobic modification, roughness engineering) and structural optimization (porous electrodes, bioinspired architectures). External field enhancements (ultrasonic, magnetic, pulsed electric) are comprehensively evaluated, showing 60 % bubble coverage reduction via ultrasonic cavitation and effective detachment in microgravity environments using magnetic fields. Special attention is given to electrochemical nanobubbles, their unique interfacial behaviors, and mitigation strategies. Finally, we outline future research directions emphasizing multiphysics modeling, rapid bubble detachment electrodes, and scalable bubble management for industrial electrolyzers. This work provides a fundamental framework for optimizing bubble dynamics to advance green hydrogen production. • Details bubble induced overpotential mechanisms and bubble detachment kinetics in water electrolysis. • Electrode engineering strategies enhance bubble detachment and reduce energy losses. • External fields accelerate bubble removal, improving mass transfer and electrochemical performance.