Stabilizing NiFe sites by high-dispersity of nanosized and anionic Cr species toward durable seawater oxidation

Electrocatalytic H2 production from seawater, recognized as a promising technology utilizing offshore renewables, faces challenges from chloride-induced reactions and corrosion. Here, We introduce a catalytic surface where OH– dominates over Cl– in adsorption and activation, which is crucial for O2 production. Our NiFe-based anode, enhanced by nearby Cr sites, achieves low overpotentials and selective alkaline seawater oxidation. It outperforms the RuO2 counterpart in terms of lifespan in scaled-up stacks, maintaining stability for over 2500 h in three-electrode tests. Ex situ/in situ analyses reveal that Cr(III) sites enrich OH–, while Cl– is repelled by Cr(VI) sites, both of which are well-dispersed and…

• NN
  National Natural Science Foundation of China

  Awards: 21927811, 22072015 and 21927811
• NS
  Natural Science Foundation of Sichuan Province

  Award: 2023NSFSC0410
• SF
  Science Fund for Distinguished Young Scholars of Heilongjiang Province

  Award: JC2018004