Interface formation and Mn segregation of directly assembled La0.8Sr0.2MnO3 cathode on Y2O3-ZrO2 and Gd2O3-CeO2 electrolytes of solid oxide fuel cells
Abstract
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.
Citation
He , S , Chen , K , Saunders , M , Quadir , Z , Tao , S , Irvine , J T S , Cui , C Q & Jiang , S P 2018 , ' Interface formation and Mn segregation of directly assembled La 0.8 Sr 0.2 MnO 3 cathode on Y 2 O 3 -ZrO 2 and Gd 2 O 3 -CeO 2 electrolytes of solid oxide fuel cells ' , Solid State Ionics , vol. 325 , pp. 176-188 . https://doi.org/10.1016/j.ssi.2018.08.016
Publication
Solid State Ionics
Status
Peer reviewed
ISSN
0167-2738Type
Journal article
Description
This work was financially supported by the Australian Research Council under the Discovery Project Scheme (project numbers: DP180100731 and DP180100568), and by the Guangdong Provincial Department of Science and Technology Agency (GDST) under the GDST-NOW Science-Industry Cooperation Program (No. 2017A050501053).Collections
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