Electroless Displacement Deposition of Nanocrystalline Al on Mg Surface from AlCl3-Emic Room Temperature Ionic Liquid

Abstract

In this paper, electroless displacement deposition of Al on Mg surface in AlCl3-1-ethyl-3-methyl-imidazolium chloride (AlCl3–EMIC) ionic liquid was reported. The electrolytic etching pretreatment of Mg substrate was employed to remove the oxide layers on the surface. The process of displacement deposition was studied by open-circuit potential (OCP) measurement. The electroless deposited Al on Mg was characterized by grazing incidence X-ray diffraction (GIXRD) and scanning electron microscope (SEM). The results showed that for the Mg substrate with oxide layer on the surface, microcrystalline Al crystals of 10-20 μm were obtained in the way of immersing the Mg directly in the ionic liquid. But for the Mg substrate with oxide layer removed, the deposited Al crystals by placing the Mg in the ionic liquid were nanocrystalline, while Al particles of 200-300 nm were deposited by placing the substrate in the glove-box with residual ionic liquid on the surface.