Abstract

Aims: Ni-Mo alloy coatings could represent a key material for several leading applications of engineering. Indeed these coatings present excellent physico-chemical characteristics such as magnetism, wear-resistance, heat-conductivity, and electrocatalytic properties.

Observations: Ni-Mo alloys have been electrowon, with a pH 5.8 sulphate catholyte containing 40 g/l Ni and Mo in the range 1-4 g/l, sodium citrate and acetic acid, at temperature in the range 25-50°C and current density in the range 10-100 mA/cm2.

Methods: A cell having cathodic and anodic compartment separated by a polypropylene membrane has been used.

Result: The effect of molybdenum ion concentration in the electrolyte, temperature and current density on coating morphology and the Ni-Mo deposit adherence on steel substrate as well as Mo content of the produced binary alloys have been investigated.

Keywords: Anomalous Co-deposition, electrowinning, metal coatings, Ni-Mo alloys, activated complex, alloy morphology.

Graphical Abstract