PtNi Nanorods Catalysts Prepared by Magnetron Sputtering for Alkaline Hydrogen Evolution Reaction

Abstract The development of cost‐effective and highly efficient catalysts for the hydrogen evolution reaction (HER), particularly in alkaline environments, is a critical challenge for hydrogen applications. One promising approach involves the alloying of noble metals with transition metals. This study presents the synthesis of PtNi nanorod catalysts, characterized by a thickness of 500 nm, which were fabricated via magnetron sputtering onto nickel foam. When evaluated in a 1 M KOH electrolyte, the Pt–Ni alloy demonstrates superior HER performance compared with both Ni and Pt, exhibiting an overpotential of 35 mV at 10 mA/cm 2 and a Tafel slope of 29 mV/dec. The enhanced catalytic activity is attributed to several factors, including a high electrochemically active surface area, increased mass activity, elevated turnover frequency, and reduced electrochemical impedance. Furthermore, the Pt–Ni catalyst maintains remarkable stability at a current density of 10 mA/cm 2 over a duration of 100 h. The improved HER performance is ascribed to the nanorod architecture, which features a high density of grain boundaries, as well as the synergistic interactions between Ni and Pt.