Nano-composite electrodes fabricated by introducing nano-sized mixed ionic and electronic conducting (MIEC) catalysts into partially-sintered micro-sized ionic conducting backbones have been used by many researchers to improve the electrochemical performance, and/or reduce the operating temperature, of Solid Oxide Cells (SOCs).¹ Unfortunately, these infiltrated electrodes have often possessed poor electrochemical performance stability.²

This presentation will review recent results showing how pre-infiltrated ceria nano-particles³ or atomic layer deposited zirconia overcoats⁴ can be used as on-board Sr getters to increase the long-term stability of La_0.6Sr_0.4Co_0.8Fe_0.2O_3-x (LSCF)-infiltrated Ce_0.9Gd_0.1O_1.95-x (GDC) SOC electrodes, without compromising initial performance. This talk will also present results showing that when combined, these surface modification techniques result in LSCF-GDC performance degradation rates that are no better than those obtained from each technique used separately. Lastly, this talk will present GDC pre-infiltration results supporting a newly-emerging consensus that Sr does not surface segregate in Sm_0.5Sr_0.5CoO_3-x (SSC) like it does in LSCF.

References

1. D. Ding, X. X. Li, S. Y. Lai, K. Gerdes and M. L. Liu, Energy Environ. Sci., 7, 552 (2014).
2. M. Shah, P. W. Voorhees and S. A. Barnett, Solid State Ionics, 187, 64 (2011).
3. Y. Zhang and J. D. Nicholas, Journal of the Electrochemical Society, 168, 024522 (2021).
4. Y. Zhang, Y. Wen, K. Huang and J. D. Nicholas, ACS Applied Energy Materials, 3, 4057 (2020).