Local-atomic environment engineering of Ni-sites for industrial hydrogen production from seawater

Abstract

Seawater electrolysis integrated with renewable energy sources represents a green and sustainable pathway for hydrogen production, yet its practical application is severely constrained by the lack of cost-effective, highly active, and scalable electrodes. Herein, we report the construction of a high-performance hydrogen evolution reaction (HER) electrode by engineering the local-atomic environment of Ni sites through vanadium oxide modification. This optimized electrode delivers current densities of 500/1000 mA cm^–2 at only 283/361 mV in alkaline seawater. Impressively, a kW-scale alkaline seawater electrolyzer achieves continuous operation at an industrial-level current up to 25 A for over 880 h with an ultra-low degradation rate of 34.1 μV h^–1. Combined experimental and theoretical investigations reveal a volcano-type relationship between the chemical state of Ni and the adsorption energy of the key intermediate H* (∆G_H*), as well as the potential of zero charge (PZC) of the electrode. Furthermore, in-situ Fourier-transform infrared spectroscopy confirms that a lower PZC promotes the formation of more free water molecules near the electrode surface, thereby facilitating the HER process. This work uncovers atomic environment-governed HER mechanisms and develops a scalable, industrially stable seawater electrolysis electrode, bridging lab-innovation to practical hydrogen production.