Cobalt and cobalt–molybdenum alloy electrodes are prepared by galvanic deposi- tion on copper substrates. In this paper, we report a study on the influence of alloying cobalt with molybdenum for the oxidation of hydrazine in 1 M NaOH aqueous solutions. The electrocatalytic properties of the electrodes are studied by cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical imped- ance spectroscopy (EIS). Scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS,) and inductively coupled plasma (ICP) analysis demonstrate that the structural features and compositions of the as-prepared Co–Mo coatings vary with the deposition conditions. Electro- chemical characterization indicates that the electrochemical properties and the electrocatalytic activity of the investigated alloys were strongly dependent on the microstructural features obtained under different deposition conditions. The over- all experimental data indicate that alloying cobalt with molybdenum metal leads to an increase of the electrocatalytic activity in hydrazine electroxidation com- pared to when using the pure cobalt electrode. High catalytic efficiencies were achieved on Co/25 at.% Mo and Co/33 at.% Mo electrodes, the latter being the best electrocatalyst for hydrazine electroxidation.
