Field-driven migration of bipolar metal particles on solid electrolytes

A metal particle, which is not electronically contacted but is electrically contacted by a purely cation conducting solid electrolyte, is driven into the direction of the anode when an external electric field is applied. The particle behaves as a bipolar electrode. During the field-driven movement, the metal particle changes its morphology and spreads across the surface. This process is studied in situ with an optical microscope and ex situ with a scanning electron microscope. It is discussed as an example of morphological instabilities in solid state transport.