In-Situ TEM Analysis of Degradation Mechanisms in Solid Oxide Electrolysis Cells Under Oxygen Deficient Conditions

Abstract

Ensuring the long-term reliability of solid oxide electrolysis cells (SOECs) requires a deeper understanding of interfacial degradation mechanisms. This study employs in-situ transmission electron microscopy (TEM) to investigate structural and compositional changes at the interface between lanthanum strontium manganite (LSM) and yttria-stabilized zirconia (YSZ) under operating conditions. Using a symmetric LSM？YSZ？LSM configuration, we observed real-time degradation phenomena, including interfacial delamination, LSM poly-crystallization, and cation segregation, particularly under oxygen-deficient environments. These changes coincided with sharp increases in cell resistance and microstructural evolution. High-resolution TEM and energy-dispersive spectroscopy (EDS) revealed directional migration of Mn cations from the B-site of the perovskite lattice, suggesting oxygen vacancy formation plays a key role in destabilizing the structure. Our findings underscore the importance of stable oxygen ion transport in mitigating electrochemical degradation. This work highlights the utility of in-situ TEM in revealing degradation pathways and informing the development of more robust SOEC materials.