Electrodeposition of zinc from a Lewis acidic zinc chloride-1-ethyl-3-methylimidazolium chloride molten salt

The electrodeposition of zinc on glassy carbon and nickel substrates was investigated in the 50.0-50.0 mol% zinc chloride-1-ethyl-3-methylimidazolium chloride molten salt. The electrodeposition of zinc on both electrodes required a nucleation overpotential. Analysis of the chronoamperometric current-time transients suggested that the electrodeposition of zinc on both substrates involved instantaneous three-dimensional nucleation with mixed diffusion and kinetic controlled growth of the nuclei. Scanning electron microscopic analysis indicated that the quality of the zinc electrodeposits is greatly enhanced by the addition of propylene carbonate as a 'cosolvent'. It was also found that the deposits produced from plating baths with higher propylene carbonate concentrations or at higher temperatures exhibited larger grain size. (C) 1999 Elsevier Science Ltd. All rights reserved.