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DOE OSTI · 2500289

A highly oxygen reduction reaction active and CO 2 durable high-entropy cathode for solid oxide fuel cells

He, Fan·Zhu, Feng·Xu, Kang·Xu, Yangsen·Liu, Dongliang·Yang, Guangming·Sasaki, Kotaro·Choi, YongMan·Chen, Yu
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Abstract

One big obstacle for the oxygen reduction reaction (ORR) electrode in solid oxide fuel cells (SOFCs) is the poor reaction activity and fast degradations caused by CO 2 poisoning. Here, in this study, we report our design of an active A-site Ca-rich high-entropy Pr 0.1875 Ba 0.1875 Sr 0.1875 La 0.1875 Ca 0.25 CoO 3-δ (PBSLC 25 C) electrode, guided by the O p-band theory. Here, when applied as a cathode in solid oxide fuel cells (SOFCs), it demonstrates high ORR activity and excellent CO 2 tolerance under realistic operating conditions. Ni-YSZ-based anode-supported cells with PBSLC 25 C cathodes demonstrate excellent peak power densities of 1.14 W cm -2 , 1.04 W cm -2 , and 0.77 W cm -2 in the air with 1%, 5%, and 10% CO 2 , respectively, at 750 °C. The engineered high-entropy PBSLC 25 C effectively diminishes the CO 2 poisoning effect and maintains active surfaces for fast oxygen exchange, as confirmed by the cell durability test in air containing CO 2 (5 and 10 vol%), Raman spectroscopy, and density functional theory calculations.

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30 DIRECT ENERGY CONVERSIONCO2 toleranceCathodeHigh-entropy perovskiteOxygen reduction reactionSolid oxide fuel cells

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He, Fan, Zhu, Feng, Xu, Kang, Xu, Yangsen, Liu, Dongliang, Yang, Guangming, Sasaki, Kotaro, Choi, YongMan, Chen, Yu. 2024-05-10. A highly oxygen reduction reaction active and CO 2 durable high-entropy cathode for solid oxide fuel cells. https://doi.org/10.1016/j.apcatb.2024.124175

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