Electrochemical instability of Ag/Sb co-deposition coupled with a magnetohydrodynamic flow

During electrodeposition of silver–antimony alloy, long-range spatial patterns appear spontaneously on a copper electrode surface. The patterns consist of small spiral waves and relatively large bands. It has been observed that the composition of the electrolyte solution varies the size of the spiral waves and that the propagation direction of the band changes under a strong magnetic field. These findings suggest that this pattern formation is sustained by flow-induced electrochemical instability. The origin of this instability is discussed in relation to the large overpotential in formation of the antimony clusters.