Abstract
The initial stage of dendritic growth by zinc electrodeposits has been studied by electrochemical scanning tunneling microscopy (STM) and computer simulation. Zinc was deposited on a highly oriented pyrolytic graphite (HOPG) electrode from a 0.01mol/L ZnSO4 solution. The zinc deposits (0.018C/cm2) grew predominantly near the step line on the HOPG. Initially, the height difference (dmax) between the highest part and the lowest part of the deposit and the average roughness of the electrode surface (Ra) increased rapidly with deposition time. It is therefore suggested that the roughness of the electrode surface increases rapidly in the initial stage of electrodeposition. The simulation reproduced the morphology of the STM image (0.02C/cm2, 20nm×20nm) and the distribution of deposit heights observed by STM agreed with the result of the simulation. It was therefore confirmed that the deposition model used in the simulation is appropriate at the initial stage of zinc electrodeposition.
