Nonlinear oscillations in electrochemical growth of Zn dendrites

Electrochemical deposition can produce interesting patterns ranging from random fractals to orderly dendrites. We have studied the electrical signals due to the deposition of Zn ions in a cell with ${\mathrm{ZnSO}}_4$ electrolyte. In the dendritic regime, the current (voltage) exhibits periodic oscillations with constant applied voltage (current). The frequency is proportional to the applied voltage V and the electrolyte concentration n. We relate this behavior to the side-branching nature of the dendrites.