Ultralow Ru-doped NiFe catalyst on stainless-steel fibers for enhanced oxygen evolution reaction in anion-exchange membrane water electrolysis

Designing high-performance, stable electrodes for the oxygen evolution reaction (OER) is essential for anionexchange membrane water electrolysis (AEMWE) in industrial-scale hydrogen production. AEMWE has not yet been commercialized due to the high cost of precious metal catalysts and unsatisfactory performance of nonprecious metal catalysts. Although various anodes are being developed to replace expensive Ir-based catalysts, low-cost catalysts that demonstrate a balance of performance and stability remain limited. In the present study, we fabricated a NiFe catalyst on a corrosion-resistant stainless-steel fiber paper substrate using a simple electrodeposition method and introduced small amounts of Ru via galvanic displacement. In half-cell tests, an enhanced overpotential of 229 mV was observed for the Ru-NiFe/SS anode at 10 mA/cm(2). Using Ru-NiFe/SS as an anode for OER in AEMWE assembled with a commercial Pt/C cathode exhibited high performance with a current density of 8.73 A cm(-2) (at 2.05 Vcell and 80 degrees C). Long-term stability tests also showed that the Ru-NiFe/SS anode had higher stability than commercial IrO2 electrodes at 1 A cm(-2) and 80 degrees C for 50 h. Therefore, Ru-NiFe/ SS can be considered an alternative to conventional Ir-based electrodes to reduce hydrogen production costs.