Nanowire-flower structured catalysts regulated by MoO42−/SO42− dual anion layers for efficient seawater electrolysis

Seawater electrolysis powered by renewable energy sources, such as solar and wind, presents a promising approach for green hydrogen production, but still faces some challenges. In this study, we developed a highly efficient seawater electrolysis catalyst, SNiFeMo@NF, featuring a unique nanowire-flower structure. SNiFeMo@NF exhibits outstanding bifunctional catalytic activity for seawater electrolysis. The introduction of sulfur to adjust the electronic structure of the catalyst, along with the incorporation of molybdate (MoO42−) to boost OH− adsorption, dramatically improved both catalytic activity and resistance to chloride-induced corrosion. In natural seawater with 6 M KOH, SNiFeMo@NF demonstrates remarkable stability, operating continuously for 300 h. At a current density of 100 mA cm−2, it achieves low overpotentials of 95 mV for the hydrogen evolution reaction (HER) and 236 mV for the oxygen evolution reaction (OER). In industrial settings (6 M KOH, 80 °C), an electrolyzer utilizing SNiFeMo@NF as the catalyst attained a current density of 100 mA cm−2 with a cell voltage of just 1.46 V. The low energy consumption of the electrolyzer, combined with its integration with solar cells, underscores the economic viability and feasibility of renewable energy-driven seawater electrolysis for hydrogen production. This study offers fresh insights into hydrogen generation via seawater electrolysis.