Advances in Surface/Interface Engineering of Under-Water Superaerophobic Electrodes for Hydrogen Evolution Reaction...

The ever-increasing consumption of fossil fuels has led to environmental crises, which accelerated the quest for sustainable hydrogen energy. Among various production routes, water electrolysis stands out as a promising approach. However, the efficiency of hydrogen evolution reaction is limited by the adhesion of gas bubbles on electrode surfaces, which blocks active sites, increases overpotential, and limits mass transfer. This review highlights the design of micro/nanostructured array electrodes to achieve underwater superaerophobicity, reducing bubble adhesion, facilitating the nucleation and rapid release of ultrasmall bubbles, thereby contributing to reduce in overpotential, faster bubble growth, enhanced mass transport, and improved catalyst stability. We summarize recent advances in fabrication strategies of such electrodes, focusing on micro/nanostructural designs, covering from 0 to 3-dimensional structures. Additionally, the role of hydrophilic gels in optimizing superaerophobicity is discussed. Finally, challenges and future directions are addressed, including bubble dynamics accurate modeling, development of high activity and stability catalysts, intelligent adaptive electrode structure and active bubble regulation, and the integration of artificial intelligence and deep learning for guided electrode design. This review aims to provide a comprehensive perspective on how superaerophobic electrode design address bottlenecks in gas-evolving electrodes, paving the way toward more efficient and economical hydrogen production.