The Role of Induced Convection in Branched Electrodeposit Morphology Selection

Abstract

Branched copper and zinc aggregates were electrodeposited at large overpotentials from unstirred binary electrolyte in a quasi‐two‐dimensional cell. The concentration field was measured during deposition by electro‐optic interferometry. Depending on deposition conditions, either natural convection or electrokinetic convection was induced at the growth tips. In the deposition of zinc dendrites, the onset of electrokinetic convection destabilized the growth tips, resulting in multiple tip splitting. The growth then restabilized into a new pattern where the branch spacing was coupled to the scale of the convection cells.