Electrodeposition of aluminum from AlCl3-triethylamine hydrochloride ionic liquid

Abstract

Aluminum chloride and triethylamine hydrochloride were employed in the synthesis of an AlCl₃-Et₃NHCl electrolyte. An aluminum sheet was utilized as the anode for the electrodeposition of metallic aluminum onto a copper substrate. This study aimed to investigate the effects of deposition potential on the morphology of the aluminum coating, the deposition mechanism, and the changes in Al(III) complex ions during the electrodeposition process. The results indicated that a deposition potential of − 0.3 V (vs. Al) produced aluminum coatings that were uniformly dense and securely adhered to the substrate. When electrodeposition occurred at − 0.5 V (vs. Al), the substrate surface exhibited aluminum nanowires with an approximate diameter of 367 nm. XRD analysis indicated a more pronounced (200) preferred orientation in the aluminum layer deposited at more negative potentials. Raman spectroscopy analysis detected the presence of AlCl₄⁻ and Al₂Cl₇⁻ anions in the AlCl₃-Et₃NHCl system before electrodeposition, followed by the formation of Al₃Cl₁₀⁻ complex ions in the system under potentiostatic control.