Self-supported bimetallic selenide heterostructure catalyst with enhanced electronic interaction for industrial-level seawater electrolysis

The successful implementation of direct seawater electrolysis for sustainable hydrogen production and seawater desalination hinges on the development of high-efficiency and durable catalysts. In this study, we report the fabrication of a self-supported bimetallic selenide heterostructure catalyst (NiSe₂-RuSe₂/NF), which achieves an ultralow overpotential of 26 mV at 10 mA cm⁻² in natural seawater (unpurified, with 1 M KOH added), outperforming commercial Pt/C. Furthermore, it exhibits exceptional long-term stability, maintaining performance over 250 h at an industrial current density of 500 mA cm⁻². Combined density functional theory (DFT) calculations and experimental analyses reveal that the heterostructure modulates the electronic structure, optimizing H* adsorption and enhancing HER catalytic activity. This work provides a straightforward yet effective strategy for designing highly active and efficient HER electrocatalysts for practical seawater electrolysis applications.