ELECTROCHEMICAL INSTABILITY OF AG SB CODEPOSITION COUPLED WITH A MAGNETOHYDRODYNAMIC FLOW/

During electrodeposition of silver-antimony alloy, long-range spatial patterns appear spontaneously on a copper electrode surface. The patte rns consist of small spiral waves and relatively large bands. It has b een observed that the composition of the electrolyte solution varies t he size of the spiral waves and that the propagation direction of the band changes under a strong magnetic field. These findings suggest tha t this pattern formation is sustained by flow-induced electrochemical instability. The origin of this instability is discussed in relation t o the large overpotential in formation of the antimony clusters. (C) 1 998 Elsevier Science B.V. All rights reserved.