Complex Morphology Of Zinc Electrolysis Sediment

With the different conditions of the electrodeposits, such as the geometry of the electrochemical cell, voltage, concentration, the gravity field, magnetic field, electrochemical deposition(ECD) provides a wide range of morphologies. It is a challenge to understand the origin of the formation of these morphologies.Using ZnSO₄ aqueous solution as the electrolyte, Zinc was deposited in the quasi two-dimensional radial electrochemical cell. The dependence of morphologies on the different conditions of the electrodeposits has been studied, and main conclusions are as follows:(1) The dependence of morphologies on voltage and concentration has been studied by the experiments of electrodeposits of Zinc. When the voltage, the numbers of the ramification and the size of the side branch are changed, the clamp of the side branch on dendrite is also altered accordingly;When the concentration of the solution is different, the morphology of the deposition is changed from the dendrite to the dense radial, which mainly depends on the concentration distributing of ions and the transport mode and speed of ions.(2) The dependence of morphologies on impurity has been studied by the experiments of Zinc electrodeposits. The new deposition will grow from not only the cathode but also the original deposition that has been put into the electrochemical cell. The growth pattern of new deposition is not affected by the original deposition and is related with the concentration and thickness of the electrolyte, the potential between the anode and the cathode;The Cu²⁺ ion and H⁺ ion have important effect on the transformation of the growth morphology in the Zinc electrodeposits.(3) The influence of a magnetic field on the microstructure of the Zinc electrodeposits obtained in a 2-dimensional concentric electrode cell is investigated. The growth fractal morphology of metal electrodeposits is dramatically altered when a static magnetic field is applied to the cell. Based on the experimental results , the mechanism of the magnetohydrodynamic(MHD) for the morphological transition is proposed. If the convection is inhibited, the morphological transition isattributed to the Hall Effect.