Trace ruthenium enables synergistic interactions in NiFeB nanosheets for industrial-current-density water oxidation

The oxygen evolution reaction (OER) represents the primary kinetic bottleneck in electrochemical water splitting, necessitating advanced electrocatalysts that combine high activity with long-term stability for industrial-scale hydrogen production. Here, we demonstrate a hierarchical Ru-decorated NiFeB nanosheet architecture (Ru@NiFeB) synthesized via sequential electrodeposition and hydrothermal processing on nickel foam substrates. The strategic incorporation of trace Ru species (~ 2 wt.%) induces favorable electronic modulation at the heterointerface, optimizing the adsorption energetics of oxygen-containing intermediates. The resulting Ru@NiFeB electrode exhibits exceptional OER performance with an overpotential of merely 235 mV at 100 mA/cm2 in 1 M KOH, outperforming commercial RuO2 catalysts. Remarkably, the electrode sustains 1000 mA/cm2 for over 150 hours in concentrated 4 M KOH electrolyte without discernible degradation, representing one of the most stable low-doped noble metal-based OER catalysts reported to date. This work provides a viable pathway toward cost-effective, robust electrocatalysts for industrial alkaline water electrolysis, advancing the feasibility of large-scale green hydrogen production.