Key Strategies for Continuous Seawater Splitting for Hydrogen Production: From Principles and Catalyst Materials to Electrolyzer Engineering

Due to the high cost of ultra-pure water supply and the mismatch between water sources and renewable energy distribution, the large-scale production of green hydrogen through seawater electrolysis has generated significant interest. This presents an attractive potential technology within the framework of carbon-neutral energy production. However, owing to the complex composition of seawater, particularly the competitive oxidation reactions and corrosion issues involving Cl-, seawater electrolysis has suffered from low selectivity and poor stability in oxygen evolution reaction (OER), which severely impact the efficiency of hydrogen production and hinder the practical applications. To further promote in-depth research and practical applications of seawater electrolysis, this review introduces the principles, key advantages, and challenges of seawater electrolysis. Specifically, the design strategies are categorized for highly active OER electrocatalysts for seawater electrolysis, including catalyst design, design of chemical reaction systems, and other special process design. To ensure long-term operational stability of seawater electrolysis, various strategies such as employing self-supporting materials, surface protection strategies, and electrolyzer design, are discussed. Finally, current challenges and future prospects for the industrialization of seawater electrolysis are proposed and discussed. It is expected that this review provides new insights for large-scale seawater-based hydrogen production in the future. The large-scale production of green hydrogen through seawater electrolysis has generated significant interest. This review covers the principles, key advantages, and electrocatalysts/electrolyzer design strategies of seawater electrolysis. The current challenges and future prospects are also proposed and discussed. image