Galvanostatically Deposited PtNi Thin‐Films as Electrocatalysts for the Hydrogen Evolution Reaction

The synthesis of hybrid platinum materials is fundamental to enable alkaline water electrolysis for cost‐effective H2 generation. In this work, we have used a galvanostatic method to co‐deposit PtNi films onto polycrystalline gold. The surface concentrations of Ni (ΓNi) and Pt (ΓPt) were calculated from electrochemical measurements; the ΓPt/ΓNi ratio and electrocatalytic activity of these materials towards hydrogen evolution reaction (HER) in 1 M KOH show a strong dependence on the current density pulse applied during the electrodeposition. Analysis of the Tafel parameters hints that, on these deposits, HER proceeds through a Volmer‐Heyrovsky mechanism. The galvanostatically deposited PtNi layers present a high current output per Pt gram, 3199 A gPt−1, which is significantly larger compared to other PtNi‐based materials obtained by more extended and more complex synthesis methods. PtNi layers were deposited onto gold electrodes using galvanostatic pulses of varying intensities to produce electrocatalysts for the hydrogen evolution reaction. These materials present an output current per Pt gram, 3199 A gPt−1, significantly larger than other PtNi‐based materials obtained by more extended and complex synthesis methods. Small additions of nickel during the co‐deposition increase the catalytic activity of the platinum deposits.