Multi-method characterizations of the native oxide layer of Al Electrodes

Because of its electro chemical properties, aluminium is seenas a possible active material for future rechargeable batteries.In this work, a deep eutectic solvent (DES) consisting of AlCl3and urea was used.In many environments, aluminium is protected form corrosionby its native oxide layer, which makes it an attractiveconstruction material. In the context of electrochemical cells, hisis a limitation. Aggressive anion containing media (e.g. Cl) cancause the breakdown of the passive oxide and lead tocorrosion. From literature it is well known, that in aqueousmedia chloride anions permeate the passive layer beforepitting.Literature on aluminum in combination with chloroaluminate ILor DES suggests, that contact between electrode andelectrolyte before electrochemical experiments, can improvethe cell performance. However, the underlying mechanism isnot know. This work will provide further insights on processesoccurring during this soaking time.