Electrochemical behavior of Al 2 O 3 /Al composite coated Al electrodes through surface mechanical alloying in alkaline media

Abstract

The behavior of Al 2 O 3 /Al composite coated Al electrodes fabricated by surface mechanical alloying 'sMA' was studied. The work was accomplished using Cyclic voltammetry and electrochemical impedance spectroscopy (EIS) techniques in alkaline media 2MKOH were done at room temperature. Results show hydroxyl ions accumulate on the surface due to Al deformation micro cavities filling with Al 2 O 3 until full charge blockage reached. A barrier cover layer development causing an increase of both resistance and capacitance as it becomes more stable and thinner with exposure time increase. Migrating hydroxyl ion inside micro cavity changed its composition from Al 2 O 3 to stable tetrahedral Al(OH) 4 ? aluminate ions. Therefore future benefits could be reached by developing such surfaces having charge accumulation that enables environmental interaction.