Electrochemical preparation and alkaline water splitting activity of ternary Co-Fe-Mo non- crystalline coatings

The influence of Na2MoO4 concentration on the electrochemical deposition of Co-Fe and Co-Fe-Mo alloy coatings from slightly acidic citrate baths and their electrocatalytic performance for alkaline water electrolysis in 1 M NaOH solution have been examined. The chemical composition and the evolution of the crystallographic structure have been analyzed by X-ray fluorescence spectroscopy (XRF), X-ray diffraction (XRD), and scanning electron microscope with energy dispersive spectroscopy (SEM-EDS) measurements. Increasing concentration of Mo in the alloy led to gradual amorphization of the crystalline structure. Electrochemical studies revealed that the cathodic Tafel slope reduced to 69 mV/ dec for Co-Fe-Mo alloys. Furthermore, a low overpotential value of-121 mV was observed from polarization studies, which confirmed a good catalytic activity for the alkaline water splitting process.(c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.