Advanced Nanoscale Characterizations of Solid Oxide Cell Electrodes

Abstract

Solid oxide cells (SOCs) have attracted a growing attention thanks to their high efficiency and ability to operate in both electrolysis (SOEC) and fuel cell (SOFC) modes. Despite its great potential, the current SOC technology faces significant cell degradation during long-term operation. The degradation phenomena are still not well understood as they involve complex and intricate processes arising at different length scales. Additionally, it has been shown that the degradation rate under SOEC operation is generally higher than in SOFC mode. To address this issue, durability tests were performed in SOEC mode at 750, 800 and 850 °C for 2000 h at -1 A cm-2 in 10/90 vol.% H2/H2O and dry air. The electrochemical performance of the cells was assessed using electrochemical impedance spectroscopy. In addition, advanced characterization techniques with nanometer and atomic resolution have been used to study material degradation after long-term testing.