About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
Advances in Materials and Systems for a Hydrogen Economy
|
| Presentation Title |
La0.6Sr0.4Co0.2Fe0.8O3 Degradation Under SOEC Conditions and Its Effects on Operational Lifetimes |
| Author(s) |
Brian P. Gorman, Heather Slomski, Madeline Van Winkle, Nicholas Strange, Liam Nagle-Cocco, Andrew Rowberg, Jonas Kaufman, Michael Dzara, David Ginley, Sarah Shulda |
| On-Site Speaker (Planned) |
Brian P. Gorman |
| Abstract Scope |
LSCF-6428 has been a common air electrode choice for SOFC and SOEC applications due to its mixed electrical and oxygen ion conductivity under operating conditions. Unfortunately, degradation of this material during operation can lead to serious losses in current density and thus hydrogen production. Our initial work has shown that although the material appears to be phase pure using lab scale XRD, synchrotron XRD and STEM show clear phase instability. Porous LSCF-6428 air electrodes decompose into Co3O4 spinels and SrO phases with LSCF-9119 being the stable perovskite phase at 750°C operating temperatures. SrO migrates quickly along pore surfaces, eventually reaching the YSZ electrolyte where deleterious zirconate phases can be formed. SrO fills microstructural pores in the electrode materials, thus reducing three phase boundaries. Spinels are less mobile but do not have the mixed ionic conductivity of LSCF phases. A proposed SOEC stack that minimizes these issues will be proposed. |