Enhancing Performance of Stabilized Bismuth Oxide-Based Cathodes via Infiltration Process for LT-SOFCs
At lower temperatures below 700 oC, however, the cathode polarization exponentially increases due to its thermally activated nature, thus dramatically decreasing the performance. Previously, stabilized bismuth oxide-based composite cathodes (ex: LSM-ESB) have been reported as promising cathodes for LT-SOFC applications with their low area specific resistance (ASR) at LT region. This high performance would be explained that LSM has low activation energy for dissociative adsorption of oxygen in ORR on its surface and that ESB has exceptionally high ionic conductivity as well as excellent surface exchange properties. Therefore, one can expect that the microstructural optimization of these cathode could further increase the cathode performance as well as enhance the their durability.
In this study, we employed the infiltration process to tailor the surface morphologies of stabilized bismuth oxide-based composite cathodes for enhancing surface activity and their stability to achieve higher SOFC performance. Through infiltration, for example, LSM was infiltrated on the porous ESB scaffold with different manners. The microstructural evolution and electrochemical performance was characterized and their cross-effect will be discussed.