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

ChemistryOpen. 2022 Feb;11(2):e202100241. doi: 10.1002/open.202100241.

Abstract

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 ΓPtNi 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.

Keywords: alkaline hydrogen evolution reaction; electrocatalysis; galvanostatic electrodeposition; platinum-nickel; water electrolysis.