Advancing direct seawater electrocatalysis for green and affordable hydrogen

By directly electrolyzing seawater and using marine energy as the power source, green hydrogen can be generated independent of freshwater and fossil fuels, representing a more sustainable pathway. However, the complex composition of seawater creates catalytic challenges that result in electrode corrosion and failure of direct seawater electrolysis, questioning the technological and economic feasibility of direct seawater splitting. In this review, we systematically analyze pressing barriers to optimizing direct seawater splitting and consider important future directions to advance techno-economic feasibilities. We reveal that selective catalysts and stable electrolyzer devices are two critical factors for efficient direct seawater electrolysis. To improve the practical and economic feasibility of direct seawater splitting, it is crucial to develop novel and low-cost electrolyzers. We conclude that developing standard testing criteria, stable electrocatalysts, and efficient in situ desalination components are the core for high-performance seawater electrolyzers.