Ali, H.; König, P.; Tran, X.Q.; Kaus, A.; Türk, H.; Hammud, A.; Gheisari, Z.; Vibhu, V.; Roddatis, V.; Schmidt, F.P.; Blume, R.; Zeller, P.; Frömling, T.; Gunkel, F.; Knop-Gericke, A.; Reuter, K.; Eichel, R.A.; Scheurer, C.; Lunkenbein, T.: Interfacial Atomic and Electronic Structures of LSM/YSZ Thin Films as Models for SOC Air Electrodes. ChemElectroChem 13 (2026), p. e202500343/1-18
10.1002/celc.202500343
Open Access Version
Abstract:
Solid oxide cells (SOCs) are highly efficient electrochemical devices, yet their high-temperature operation induces structural instabilities that limit long-term performance. Thin-film electrodes provide a model platform to probe such effects due to their well-defined geometry and chemistry. Here, we combine high-resolution electron microscopy, synchrotron X-ray spectroscopy, and density functional theory to investigate the thermal stability of epitaxial lanthanum–strontium manganite (LSM) films on yttria-stabilized zirconia (YSZ). Comparing ultrathin (5 nm) and thick (200 nm) films under sintering (1150°C) and operating (800°C) conditions, we identify distinct degradation pathways: thick films remain largely stable but form interfacial La2Zr2O7 , while ultrathin films gradually dewet and aggregate, underscoring their instability as model electrodes. Furthermore, we show that the LSM bulk favors the less conductive rhombohedral phase, whereas, at the LSM/YSZ interface, a cubic-like LSM polymorph with enhanced electronic transport is stabilized, accompanied by oxygen vacancies, Mn2+ enrichment, and cation disorder. These insights provide design principles for stabilizing interfaces to improve the efficiency and durability of SOCs.