Effect of nicotinamide on electrodeposition of Al from aluminium chloride (AlCl3)-1-butyl-3-methylimidazolium chloride ([Bmim]Cl) ionic liquids

Abstract

The effect of nicotinamide on the electrodeposition of Al was first investigated in the ionic liquid [Bmim]Cl/AlCl3 (40.0/60.0, mol%) by means of cyclic voltammetry and chronopotentiometry. Cyclic voltammograms indicated that nicotinamide produced an inhibiting effect on Al deposition, which can be attributed to the adsorption of nicotinamide on the electrode surface. Galvanostatic deposition experiments revealed that nicotinamide served as a very effective leveling agent, resulting in highly uniform and smooth Al deposits. The effects of temperature and current density on the surface morphologies and crystal orientations of Al deposits were also studied. As the temperature was increased from 30 to 70 A degrees C, the grain size of Al deposits increased but the intensity of the preferred (200) crystallographic plane weakened. By contrast, the opposite applied just with increasing current density from 3.4 to 9.4 mA cm(-2).