Anode deactivation over prolonged SOFC operation represents a major issue towards stable and reliable energy production from hydrocarbon-containing fuels. In this respect, Ni-YSZ replacement with oxide-based anodes, less prone to coking, is commonly regarded as a viable solution. Nevertheless, most studied oxides cannot compete with Ni-based state-of-the-art anodes in terms of conductivity and catalytic activity. In this work a novel MIEC anodic composite based on La0.6Sr0.4Fe0.8Mn0.2O3-δ (LSFMn) perovskite and Ce0.85Sm0.15O2-δ containing 5 wt.% of Ni (NiSDC) was tested in dry methane. In reducing conditions, LSFMn undergoes phase transformation to Ruddlesden-Popper structure, exsolving Fe0 nanoparticles and retaining proper conductivity. The small amount of Ni, well-dispersed on the SDC matrix, forms a Ni-Fe alloy with the exsolved iron from the perovskite. While Ni-Fe alloy activates CH4, SDC provides enough O2− ions to electrochemically oxidize any cracking products. Endurance cell test at 800°C in dry CH4 shows a stable current density output for over 33h and both SEM and Raman Spectroscopy do not reveal any anode fouling.
|Titolo:||Electrochemical performance and stability of LSFMn+NiSDC anode in dry methane|
|Data di pubblicazione:||2020|
|Appare nelle tipologie:||1.1 Articolo in rivista|