Nickel Deposition from a Watts Bath Containing Monosodium Glutamate

Abstract

Nickel electrodeposition onto copper substrates was carried out from a Watts bath in the presence of monosodium glutamate (MSG) as a complexing agent. The study dealt with the influence of MSG concentrations on the cathodic current efficiency, cathodic polarization curves, anodic linear stripping voltammetry and the throwing power as well as the throwing index of the bath. The presence of MSG resulted in a marked shift in the polarization curves towards more negative potential values, indicating an inhibition of Ni+2 ion deposition. On the other hand, the extent of the inhibition increased with increasing MSG concentration. The addition of MSG improved the appearance of nickel deposited from the Watts bath. Moreover, the throwing power increased by a factor of more than three in the presence of MSG. The surface morphology of the nickel plated with and without MSG was examined using scanning electron microscopy (SEM), while the microstructure was examined using x-ray diffraction (XRD).