TY - JOUR

T1 - Cobalt-free high-entropy perovskite La0.2Pr0.2Nd0.2Sm0.2Sr0.2FeO3-δ solid oxide cell air electrode with enhanced performance

AU - Pretschuh, Patrick

AU - Egger, Andreas

AU - Paulachan, Priya

AU - Schöggl, Johanna

AU - Brunner, Roland

AU - Bucher, Edith

N1 - Publisher Copyright: © 2024 The Author(s). Fuel Cells published by Wiley-VCH GmbH.

PY - 2024/6/26

Y1 - 2024/6/26

N2 - This study investigates the novel cobalt-free high-entropy perovskite, La 0.2Pr 0.2Nd 0.2Sm 0.2Sr 0.2FeO 3–δ (LPNSSF), as an air electrode material for solid oxide cells (SOCs). When testing a button cell with a single-phase LPNSSF electrode, a current density of 0.55 A cm −2 is obtained at 0.7 V in fuel cell mode at 800°C. In order to mitigate the moderate electronic conductivity of LPNSSF, two approaches are explored. Incorporating a Co-free highly conductive perovskite, LaNi 0.6Fe 0.4O 3–δ (LNF), either as an LPNSSF–LNF composite electrode or as a current collector layer (CCL), enhances the performance to 0.61 and 0.66 A cm −2, respectively, under the same conditions. Microstructural features are studied by electron microscopy and show a rather dense structure of the CCL. Optimization of the current collector increases the current density further to 0.96 A cm −2 at 0.7 V in a 5 × 5 cm 2 anode-supported cell at 800°C. This cell exhibits good long-term stability in electrolysis mode in H 2-H 2O with 80% humidification. Continuous polarization of −0.69 A cm −2 is sustained for 1000 h, with an average degradation rate of 10 mV kh −1 after an initial run-in phase. These findings demonstrate the promising performance and durability of LPNSSF as cobalt-free SOC air electrode.

AB - This study investigates the novel cobalt-free high-entropy perovskite, La 0.2Pr 0.2Nd 0.2Sm 0.2Sr 0.2FeO 3–δ (LPNSSF), as an air electrode material for solid oxide cells (SOCs). When testing a button cell with a single-phase LPNSSF electrode, a current density of 0.55 A cm −2 is obtained at 0.7 V in fuel cell mode at 800°C. In order to mitigate the moderate electronic conductivity of LPNSSF, two approaches are explored. Incorporating a Co-free highly conductive perovskite, LaNi 0.6Fe 0.4O 3–δ (LNF), either as an LPNSSF–LNF composite electrode or as a current collector layer (CCL), enhances the performance to 0.61 and 0.66 A cm −2, respectively, under the same conditions. Microstructural features are studied by electron microscopy and show a rather dense structure of the CCL. Optimization of the current collector increases the current density further to 0.96 A cm −2 at 0.7 V in a 5 × 5 cm 2 anode-supported cell at 800°C. This cell exhibits good long-term stability in electrolysis mode in H 2-H 2O with 80% humidification. Continuous polarization of −0.69 A cm −2 is sustained for 1000 h, with an average degradation rate of 10 mV kh −1 after an initial run-in phase. These findings demonstrate the promising performance and durability of LPNSSF as cobalt-free SOC air electrode.

KW - cobalt-free air electrode

KW - current collector layer

KW - electrochemical impedance spectroscopy

KW - high-entropy perovskite

KW - long-term stability

KW - solid oxide electrolyzer cell

KW - solid oxide fuel cell

UR - http://www.scopus.com/inward/record.url?scp=85196866752&partnerID=8YFLogxK

U2 - 10.1002/fuce.202400068

DO - 10.1002/fuce.202400068

M3 - Article

VL - 24.2024

JO - Fuel Cells

JF - Fuel Cells

SN - 1615-6846

IS - 3

M1 - e202400068

ER -