Galvanic deposited Ni-Ir electrocatalyst for electrolysers

•Alkaline water splitting requires improved catalysts for the hydrogen evolution.•Electrochemical production route for nanoscale iridium-nickel catalyst.•Oxalic acid as complexing agent for galvanic process.•Alloy-composition from 6 to 70% iridium, with best catalytic results for 70% Ir. In this study, iridium- nickel- catalysts were galvanostatically prepared from different iridium salts. The influence of deposition parameters and bath composition on surface morphology, alloy composition and catalytic properties for the hydrogen evolution reaction was determined. Oxalic acid was determined as complexing agent and improved the iridium incorporation rate and efficiency. The achieved alloy compositions ranged from 6% to 70% iridium, with best results for the hydrogen evolution reaction (HER) coming from an electrode with 70% iridium.