V doped NiFeP via defect engineering for anion exchange membrane seawater electrolysis under industrial conditions

The development of highly efficient, corrosion-resistant and structurally stable non-precious metal catalysts remains the core challenge in advancing the industrialisation of anion exchange membrane (AEM) water/seawater electrolysis technology. In this study, a self-supported bifunctional electrode (V–NiFeP-Plasma) was successfully constructed to efficiently promote alkaline water and seawater electrolysis through a combination of vanadium (V) doping, phosphatisation, and plasma treatment. V doping and defect-rich surface synergistically enhance the hydrogen and oxygen evolution reaction kinetics by modulating the electronic structure and inducing the generation of high-valence Ni 3+ species. Additionally, the phosphorylation surface layer effectively inhibits Cl − adsorption and penetration through electrostatic repulsion, providing excellent corrosion resistance in alkaline seawater with a corrosion current density as low as 9.64 × 10 −4 mA cm −2 . In 1 M KOH and alkaline seawater electrolytes, the V–NiFeP-Plasma-based AEM electrolyser achieves industrial-grade current densities of 500 mA cm −2 at 1.92 and 1.94 V, and operates stably for 500 and 110 h, respectively, with a performance degradation rate of <5%. The corresponding to hydrogen production energy consumption is 4.59 and 4.64 kWh/Nm 3 with a hydrogen cost 1.02 and 1.03 USD/kg H 2 . This study provides new ideas for the design of industrial-grade catalysts for AEM water/seawater electrolysis. • V–NiFeP-Plasma drives AEM seawater electrolysis with outstanding performance and durability. • Vanadium doping and plasma treatment optimize electronic structure and surface defects. • The phosphorylation surface layer effectively inhibited the Cl − attack through electrostatic interactions.