DEPOSITION OF ZN-CO BY CONSTANT AND PULSED CURRENT

The initial stages of both Zn-Co and Zn electrodeposition were investi gated by electrochemical quartz crystal microgravimetry (EQCM). The in itial electrode mass growth, determined under both pulse and constant current conditions, was much higher than predicted by Faraday's law. T his was explained in terms of the precipitation of scarcely soluble co mpounds of zinc on an electrode surface. The EQCM data confirm that th e hydroxide suppression mechanism explains the anomalous Zn and Co cod eposition. A nonuniform adsorption of brightener (benzalaceton) on the profiled surface was concluded on the basis of plating distribution i nvestigations. The additive adsorbs to a greater extent on the surface projections.