Robust Aluminum Electrodeposition from Iionic Liquid Electrolytes Containing Light Aromatic Naphta as Additive.

Abstract

Aluminum electrodeposition can be carried out from several ionic liquid electrolyte formulations. Nevertheless, this plating process has not been industrialized so far because of the durability of the electrolytes and because the Al coatings obtained are non‐fully homogeneous in terms of coating morphology and thickness distribution. In this work we electrodeposited Al coatings from a 3‐butyl‐1‐ethylimidazolium tetrachloroaluminate electrolyte additivated with increasing concentrations of a new cost‐effective additive: light aromatic naphtha solvent. Firstly, electrolytes were characterized by cyclic voltammetry, where changes in the electrochemistry of the process were identified. Then, surface characterization showed that Al coatings morphology turned out to be smoother, more homogeneous and more compact with increasing additive concentration. Furthermore, the process was scaled up to flat plates of 18 cm2 area and also on 25 cm2 parts designed with straight corners to demonstrate both the optimization of the electrolytic bath performance and its throwing power enhancement.