Interface formation and Mn segregation of directly assembled La0.8Sr0.2MnO3 cathode on Y2O3-ZrO2 and Gd2O3-CeO2 electrolytes of solid oxide fuel cells
© 2018 The establishment of intimate electrode/electrolyte interface is very important in solid oxide fuel cells (SOFCs), because it plays a critical role in the overall cell performance and durability. In this study, Mn segregation and interface formation between directly assembled La0.8Sr0.2MnO3(L...
| Main Authors: | , , , , , , , |
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| Format: | Journal Article |
| Published: |
Elsevier BV * North-Holland
2018
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| Online Access: | http://purl.org/au-research/grants/arc/DP180100568 http://hdl.handle.net/20.500.11937/72631 |
| Summary: | © 2018 The establishment of intimate electrode/electrolyte interface is very important in solid oxide fuel cells (SOFCs), because it plays a critical role in the overall cell performance and durability. In this study, Mn segregation and interface formation between directly assembled La0.8Sr0.2MnO3(LSM) electrode and yttrium-stabilized zirconia (YSZ) or gadolinium-doped ceria (GDC) electrolytes are studied using combined focused ion beam and scanning transmission electron microscopy (FIB-STEM). In the case of LSM/YSZ and LSM/GDC electrodes, a significant reduction in the electrode ohmic resistance is observed after cathodic polarization at 900 °C and 500 mA cm-2, indicating the formation of an intimate interface. However, LSM particles start to disintegrate at the electrode/electrolyte interface with the increase of polarization time in the case of LSM/YSZ electrode. On the other hand, the LSM/GDC interface is very stable with negligible microstructure change at the interface. Mn segregation from the LSM perovskite structure is identified under the influence of polarization in both LSM/YSZ and LSM/GDC electrodes. The results demonstrate that nature of the electrolyte plays a critical role in the electrochemical activity, microstructure, morphology and stability of LSM/electrolyte interface under SOFC operation conditions. |
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