Non-uniform electrodeposition of zinc on the (0001) plane

Transition of zinc morphology and crystallographic orientations with increasing charge capacity is examined to identify the origin of non-uniform electrodeposition. Galvanostatic charge experiments for zinc are carried out for both polycrystalline and oriented zinc substrates to investigate the effects of electrodeposited zinc on electrodepositing zinc. The results show that the crystallographic orientations of the zinc substrates strongly affect the morphology of the electrodeposited zinc. Non-uniformity appears in the (0001)-oriented case prior to the polycrystalline, 101¯0- and 21¯1¯0-oriented cases. The (0001) plane initiates non-uniform zinc electrodeposition even in the polycrystalline case. It is attributed to the high density and low diffusivity of the ad-atom on the wide terrace structure. It is also indicated that porous structure appears from aggregated hexagonal hillocks with random orientations which initially are oriented hexagonal hillocks.