Toward Energy-Efficient Alkaline Water Electrolysis: Advances in Mass Transport Optimization and Electrolyzer Design

Alkaline water electrolysis (AWE) offers a promising route for scalable renewable hydrogen production but is constrained by significant multiscale mass-transport challenges that limit its efficiency and durability. Recent advances in hierarchical membrane structures, gradient porous electrodes, and optimized flow-field designs have enhanced ionic conductivity, gas separation, and electrolyte distribution. Concurrently, innovative bubble-management strategies, including surface modifications and external-field assistance, effectively mitigate gas-induced transport bottlenecks. Looking forward, emerging intelligent interface platforms that integrate adaptive materials, embedded sensors, and AI-driven digital twins promise real-time mass transport control and predictive system optimization. This review synthesizes critical progress and outlines future pathways, emphasizing that integrated materials-to-system approaches are essential for advancing robust, efficient, and economically viable hydrogen production.