Optimizing Nickel–iron nanostructure over large surface areas is critical. This study fabricates well-aligned Ni–Fe nanowires on nickel foam, aiming to improve catalytic activity, charge transport, and durability. Using two ferrite permanent magnets during chemical bath deposition, the approach yielded uniform NWs (55–64 nm) compared to disordered morphologies (150–180 nm) formed without magnetic guidance. Characterization via field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and electrochemical impedance spectroscopy (EIS) confirmed improved nanostructure alignment and reduced charge transfer resistance from 20 Ω to 5.2 Ω. Electrochemical performance tests depicted an overpotential of 230 mV 1.46 V vs. the reversible hydrogen electrode (RHE) at 10 mA/cm2 and a Tafel slope of 54 mV.dec-1, indicating efficient Oxygen Evolution Reaction (OER) kinetics. The electrochemically active surface area increased to 300 cm2, which was over 7.5 times greater than that of the substrate (by 40 cm2), enhancing reaction interfaces. Durability was validated by a minimal 3 mV change over 12 h at 0.5 A/cm2 and a negligible 0.01 V shift in steppotential tests.

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