The Electrodeposition of Copper and Nickel in the Acidic Room-Temperature Aluminum Chloride-1-Methyl-3-ethylimidazolium Chloride Molten Salt

Abstract

The electrodeposition of copper and nickel was investigated at polyciystalline platinum, gold, and tungsten and at glassy carbon electrodes in the acidic 66.7–33.3 mole percent aluminum chloride-1-methyl-3-ethylimidazoIium chloride molten salt. The electrodeposition of these metals at platinum and gold is complicated by underpotential deposition phenomena whereas the electrodeposition of these metals at glassy carbon and tungsten requires a significant nucleation overpotential. Dimensionless experimental current-time transients recorded at glassy carbon and tungsten are in good agreement with theoretical models based on three-dimensional nucleation with diffusion-controlled growth of the nuclei. The reduction of nickel(II) on nickel in this molten salt appears to involve the concurrent formation of a soluble nickel species.