Changes in the morphology and the composition of the Ag|Gd0.2Ce0.8O1.9 interface caused by polarization

The behavior of silver as the solid oxide fuel cell SOFC cathode material was investigated. Ag|Gd0.2Ce0.8O1.9 half cells were cathodically polarized at the temperatures between 300 and 700 °C at the potential of −0.5 V. Changes in the morphology and electronic states of the electrolyte surface on the cathodic side were examined by the Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy. Silver deposits arose around the point where electrodes contact the electrolyte. The negative polarization did not change electronic states of cerium and gadolinium in the electrolyte surface region. The mechanism of the silver migration is proposed.