Advances in catalyst design and system optimization for seawater electrolysis

Seawater electrolysis for hydrogen (H 2 ) production, using abundant seawater as feedstock and renewable electricity as the driving source, provides new opportunities for flexible energy conversion/storage and eliminates the volatility of renewable energy sources. However, the complex chemical environment of seawater has brought great challenges to the design of catalysts for seawater electrolysis, and the actual performance of catalysts for seawater electrolysis at the electrolyzer level is not satisfactory. At present, many reviews mainly focus on the design of electrocatalysts for the electrolysis of seawater, and do not consider the extension from the catalyst, specific reaction and to the specific electrolyzer application. To bridge this gap, we systematically evaluate the design of catalysts for seawater electrolysis, the regulation of electrolytes, the latest advances in electrolyzers, and the application of hybrid seawater electrolysis. By discussing key bottlenecks, corresponding regulatory strategies, and various electrolyzer designs and applications, we highlight unique design strategies for catalysts that address the different challenges of anode and cathode. In addition, the avoidance of side reactions in seawater electrolysis can be achieved through the regulation of the electrolyte, the design of the catalyst needs to be consistent with the specific device configuration, and other applications of hybrid seawater electrolysis are summarized that will contribute to the actual development of seawater electrolysis. • Tailored catalyst design strategies are highlighted to address anode and cathode challenges in seawater electrolysis. • Various electrolyzer designs and applications are discussed to advance the practical development of seawater electrolysis. • The benefits of hybrid seawater electrolysis for pollutant removal and value-added fuel/chemical production are summarized. • Key challenges and future prospects of seawater electrocatalysis technologies are outlined.