Investigation of the electrodeposition kinetics of Ni-Mo alloys in the presence of magnetic field

In the preliminary paper, devoted to the study of magnetic field effects on the catalytic properties of nickel molybdenum (Ni-Mo) system for hydrogen evolution reaction (HER), we have shown that the main effect of a magnetic field is related to the deposits surface modifications. In the present paper the electrodeposition kinetics of Ni-Mo was investigated, using electrochemical impedance spectroscopy (EIS) and polarization curves methods with and without magnetic fields. The reaction path was proposed to account for the main features of the deposition kinetics (polarization curves and impedance diagrams). This involves the reduction of Ni(II) and Mo(IV) complexed species into compounds that can be included as a whole into the deposit or decomplexed to product alloys deposits. In both cases the charge transfers reactions occurred in more than two steps, coupled by adsorbed intermediates. The proposed model can also account for the current density dependency upon the potential value and the magnetic field intensity. (C) 2014 Elsevier B.V. All rights reserved.