Abstract
Sluggish reaction kinetics on oxygen electrodes at reduced temperatures (<750 °C) remain a major challenge for the technical progress of reversible solid oxide cells (SOCs). To overcome this issue, the development of highly active and stable oxygen electrodes at intermediate temperatures (ITs, <750 °C) is urgent and essential. Rare earth-stabilized bismuth oxides are known to have high ionic conductivity and fast oxygen surface kinetics. Despite these advantageous properties, unlike conventional zirconia- or ceria-based materials, stabilized bismuth oxides have not been widely investigated as oxygen electrode components for reversible SOC applications. Herein, using the double doping strategy, we successfully developed Dy and Y co-doped Bi2O3 (DYSB), which showed record-high conductivity, ∼110 times higher than that of yttria-stabilized zirconia (YSZ) at ITs. This DYSB combined with conventional La0.8Sr0.2MnO3-δ (LSM) significantly enhanced surface diffusion and incorporation of oxygen ion kinetics during the oxygen reduction reaction (ORR). Finally, the novel LSM-DYSB oxygen electrode was simply embedded in a YSZ electrolyte-based cell without a buffer layer. The LSM-DYSB SOC yielded an extremely high performance of 2.23 W cm-2 in fuel cell mode as well as 1.32 A cm-2 at 1.3 V in electrolysis mode at 700 °C, along with excellent long-term and reversible stabilities. This study demonstrates that the novel DYSB-based electrode has great potential as a high-performance oxygen electrode for next generation SOCs and provides new insight into rational design and material selection for solid state energy conversion and storage applications.
Original language | English |
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Pages (from-to) | 20558-20566 |
Number of pages | 9 |
Journal | Journal of Materials Chemistry A |
Volume | 7 |
Issue number | 36 |
DOIs | |
State | Published - 2019 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2019 The Royal Society of Chemistry.
Funding
This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (20173010032120). This work also has supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT; The Ministry of Science and ICT) (No. 2019M3E6A1066426). This work also was supported by the DGIST Undergraduate Group Research Program (UGRP) grant.
Funders | Funder number |
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DGIST Undergraduate Group Research Program | |
MSIT | |
UGRP | |
Ministry of Trade, Industry and Energy | 20173010032120 |
National Research Foundation of Korea | |
Ministry of Science ICT and Future Planning | 2019M3E6A1066426 |
Korea Institute of Energy Technology Evaluation and Planning |