Challenges and strategies in catalysts design towards efficient and durable alkaline seawater electrolysis for green hydrogen production

Seawater electrolysis offers a sustainable solution for hydrogen production by utilizing ocean water as an electrolyte. However, the chlorine evolution reaction (ClER) and the accumulation of magnesium and calcium precipitates pose significant challenges to efficiency and durability. ClER competes with the oxygen evolution reaction (OER), reducing hydrogen output and accelerating electrode degradation, while precipitate formation on the cathode blocks catalytic sites and impairs long-term performance. Anion exchange membrane water electrolyzers (AEMWEs) tackle these challenges by leveraging alkaline media to suppress ClER and enhance catalyst stability. Recent advances in selective catalysts, protective coatings, and alternative oxidation reactions further improve reaction selectivity and energy efficiency. Additionally, strategies such as surface engineering and pH modulation mitigate precipitate formation, ensuring stable operation. Scaling these innovations into AEMWE systems demonstrates their potential for industrial-level hydrogen production. By overcoming fundamental challenges and practical barriers, seawater electrolysis advances toward commercial deployment and a sustainable energy future.