Electrochemical deposition of zinc from deep eutectic solvent on barrier alumina layers

摘要

The direct use of high-ordered porous templates of anodic aluminium oxide for formation of nanostructures via electrochemical deposition is difficult because the presence of the of barrier alumina layer in the bottom of pores. In this paper, zinc electrodeposition from a solution of ZnCl2 in a choline chloride/ethylene glycol eutectic mixture on dense alumina layers of different thicknesses was studied. In a potentiostatic regime, the deposition on a barrier layer was found to be hardly possible even when the layer is a native alumina film (about 2 nm thick). Choline and ethylene glycol form an adsorbed stable layer at the alumina/electrolyte interface and thereby block the access of zinc chloride anions to the electrode.