Magnesium was underpotentially deposited on aluminium electrodes from
magnesium nitrate-ammonium nitrate melts at temperatures ranging from 390 K
to 500 K. Electrochemical techniques used were linear sweep voltammetry and
potential step. Electrodes were studied by Scanning electron microscopy
(SEM), Energy dispersive spectrometry (EDS), energy dispersive X-ray
spectroscopy (EDX) and X-ray diffraction (XRD). It was found that reduction
processes of nitrate, nitrite and water (when present), in the underpotential
range studied, took part simultaneously with magnesium underpotential
deposition. Consequently, magnesium UPD reduction and stripping voltammetry
peaks were not pronounced and well defined. Nevertheless, EDS, EDX and XRD
measurements showed evidence of Mg2Al3, MgAl2 and Al12Mg17 alloys formed by
underpotential deposition of magnesium onto aluminium substrate.