Strategies for Designing Advanced Transition Metal-Based Electrocatalysts for Alkaline Water/Seawater Splitting at Ampere-Level Current Densities

Developing low-cost electrocatalysts with high current density (≥1000 mA cm–2) and long-term durability (≥1000 h), especially at low overpotentials (<300 mV), is essential for sustainable hydrogen (H2) production on a large-scale via alkaline water/seawater splitting. Along the way, numerous innovative ideas have been proposed to design high-performance transition metal (TM)-based electrocatalysts that meet the requirements of industrial applications. To promote development from laboratory to commercial use in this promising field, it is of great significance to summarize and organize the accumulated knowledge in time. This review begins with the fundamentals of alkaline freshwater/seawater electrolysis, providing theoretical guidance for the design of high-performance electrocatalysts. Special attention is given to effective strategies for enhancing intrinsic activity, extending stability, and improving corrosion resistance of TM-based electrocatalysts. Finally, individual perspectives on future opportunities and challenges are highlighted.