Morphological Evolution in Zinc Electrodeposition

Abstract

We present an experimental study of the electrodeposition of zinc in a thin layer, three‐electrode electrochemical cell. We show that as the steady‐state current‐potential behavior approaches mass transfer limited kinetics, the fractal dimension of the morphology of the deposit converges to the DLA value of 5/3 . We also compare the evolution of the growth patterns with and without supporting electrolyte.

Sharp-interface model of electrodeposition and ramified growth

“…For well over a century it has been known, however, that the layer deposited during electrodeposition is prone to morphological instabilities, leading to ramified growth of the electrode surface. Over the years, many experimental, theoretical, and numerical studies have been devoted to increasing the understanding of this ramified growth regime [12][13][14][15][16][17][18][19][20]. Big contributions to our understanding of the growth process have come from diffusion-limited aggregation (DLA) models [21,22] and, more recently, phasefield models similar to those that have successfully been applied to solidification problems [23][24][25][26][27][28][29].…”

Growth of electrolytic copper dendrites. I: Current transients and optical observation

“…The optical observation is simplified as the copper growth is practically two-dimensional although it is not made in a thin layer cell [26][27][28][29][30][31][32]. This first approach also allows a study of the general behaviour of the system to be carried out.…”

Fingerlike Aggregates in Thin-Layer Electrodeposition

“…Here we report on our striking experimental discovery of fingering development in a completely unexpected scenario, that of thin-layer electrochemical deposition (ECD). Different from the most characteristic ECD morphologies, from the disordered fractals to the regularly patterned branching aggregates [4][5][6][7][8][9][10][11][12][13][14][15][16], the deposits obtained in these experiments show a small scale filament structure, which fills space densely, and is enclosed by a fingerlike, long-wavelength modulated envelope (Fig. 1).…”

“…In contrast, experiments with electrolyte solutions containing added nondepositing cations, such as those reported here, are scarce in the literature [14][15][16]. Specifically, our thin-layer experimental cell, with thickness around 100 mm, is filled with a copper salt (typically 5 3 10 22 M CuSO 4 ) containing a small amount of an alkaline salt with the same anion (normally Na 2 SO 4 ) at concentrations comprised between 10 23 M and 10 22 M. After some induction time and under constant and moderately high applied potentials, commonly between 10 and 30 V, well-formed fingers such as those shown in Fig.…”