A new method for practical electrodeposition of aluminium from ionic liquids

• For the first time we electrodeposited Al from ionic liquids outside glove box.
• Uniform and adherent Al layers were deposited onto mild steel substrates.
• Adherence of Al to steel was significantly enhanced by in-situ electro-etching.

Successful electrodeposition of aluminium from ionic liquids has been long achieved scientifically. Nevertheless, standard industrial procedures have not yet been established due to the difficulties associated with using closed system filled with inert gas for the electrodeposition process. This paper presents a new methodology in which electrodeposition of aluminium is conducted in air, after preparation of ionic liquids in a glove box and covering them by a nonwater-absorbable layer of particular organic compound. This compound is stable and shows no reaction with the ionic liquid. Using this new methodology, functional aluminium layers were successfully deposited from a first generation ionic liquid AlCl3/1-ethyl-3-methylimidazolium chloride – [EMIm]Cl – (60/40 mol%) on low carbon steel. Cyclic voltammetry (CV) measurements revealed that there was no significant difference in electrochemical properties characteristic of Al deposition when conducted in open air. SEM/EDX assessments showed that uniform, dense and adherent Al layers were obtained. Adherence of Al to the steel substrate was improved via in-situ electrochemical etching.

Fig. 1. Photograph of a beaker containing AlCl3/[EMIm]Cl ionic liquid previously prepared in the glove box and insulated from air by a floating layer of decane, in addition to Al electroplated steel strip.Figure optionsDownload as PowerPoint slide