Electrodeposition of aluminium from ionic liquids:: Part I -: electrodeposition and surface morphology of aluminium from aluminium chloride (AlCl3)-l-ethyl-3-methylimidazolium chloride ([EMIm]Cl) ionic liquids

The electrodeposition and surface morphology of aluminium on tungsten (W) and aluminium (Al) electrodes from 2:1 molar ratio AlCl3-[EMIm]Cl ionic liquids were investigated. Analyses of the chronoamperograms indicate that the deposition process of aluminium on W substrates was controlled by instantaneous nucleation with diffusion-controlled growth, while the deposition processes of aluminium on Al electrodes were found to be associated with kinetic limitations. Constant potential deposition experiments showed that the electrodeposits obtained on both W and Al electrodes between -0.10 and -0.40 V (vs. AI(III)/Al) are dense, continuous and well adherent. Dense aluminium deposits were also obtained on Al substrates using constant current deposition between 10 and 70 mA/cm(2), and the current efficiency was found to be dependent of the current density varying from 85% to 100%. (c) 2005 Elsevier B.V. All rights reserved.