In situ study the dependence of electrochemical migration of tin on chloride

The dependence of electrochemical migration (ECM) of tin on chloride was investigated using in situ electrochemical and optical techniques. An interesting phenomenon is first found that tin dendrite grows not only in the electrolyte layer with low chloride concentration but also in the electrolyte layer with high chloride concentration, although it is generally suggested that the growth of tin dendrite through ECM is not available in solution with high chloride concentration. Mechanisms have been proposed to explain the ECM of tin in the electrolyte layer with various chloride concentrations.

► Electrochemical migration was first investigated under thin electrolyte layer.
► The dependence of ECM on chloride was clarified.
► Tin dendrite can be observed in electrolyte with high chloride concentration.
► More chloride in electrolyte layer, more OH− ions will be created on the cathode.