Electrodeposition of Mo/MoOx Thin Film on Nickel Substrate From Dimethyl-Sulfoxide: Assessing Electrolytic Bath Characteristics

Non-stoichiometric mixed-valent molybdenum oxide (MoOx) films were deposited on nickel substrates by electrodeposition from dimethyl-sulfoxide (DMSO) solution. Different experimental electrodeposition parameters (i.e., supporting electrolyte concentration and small amounts of water on the electrolytic bath) have been assessed in order to analyze their influence on the mechanism of induced Mo/MoOx deposition. Cyclic voltammetry was used to assess the electrochemistry of the process while morphological changes of the deposited films were monitored by scanning electron microscopy (SEM). SEM images of the molybdenum oxide film show that the characteristic snowed structure on the film surface become more prevalent during the transition from the oxidized state to the reduced state without signification change in the Root Mean Square (RMS) surface roughness value. Furthermore, energy dispersive (X-ray) spectroscopy (EDS) studies show that the presence of water in the electrolytic bath has great effect on the morphology of the films.