It was recalled that a metallic particle, which was in electrical contact with a purely cation-conducting solid electrolyte, was driven in the direction of the anode when an external electric field was applied: the particle behaved as a bipolar electrode. During the field-driven movement, the metal particle changed its morphology and spread across the surface. This process was studied in situ using an optical microscope and ex situ using a scanning electron microscope. It was considered to be an example of morphological instability during solid state transport.

Field-Driven Migration of Bipolar Metal Particles on Solid Electrolytes. K.Peppler, C.Reitz, J.Janek: Applied Physics Letters, 2008, 93[7], 074104