A-site deficient semiconductor electrolyte Sr1−xCoxFeO3−δ for low-temperature (450-550 °C) solid oxide fuel cells

Thumbnail Image
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Degree programme
RSC Advances, Volume 12, issue 38
Fast ionic conduction at low operating temperatures is a key factor for the high electrochemical performance of solid oxide fuel cells (SOFCs). Here an A-site deficient semiconductor electrolyte Sr1−xCoxFeO3−δ is proposed for low-temperature solid oxide fuel cells (LT-SOFCs). A fuel cell with a structure of Ni/NCAL-Sr0.7Co0.3FeO3−δ-NCAL/Ni reached a promising performance of 771 mW cm−2 at 550 °C. Moreover, appropriate doping of cobalt at the A-site resulted in enhanced charge carrier transportation yielding an ionic conductivity of >0.1 S cm−1 at 550 °C. A high OCV of 1.05 V confirmed that neither short-circuiting nor power loss occurred during the operation of the prepared SOFC device. A modified composition of Sr0.5Co0.5FeO3−δ and Sr0.3Co0.7FeO3−δ also reached good fuel cell performance of 542 and 345 mW cm−2, respectively. The energy bandgap analysis confirmed optimal cobalt doping into the A-site of the prepared perovskite structure improved the charge transportation effect. Moreover, XPS spectra showed how the Co-doping into the A-site enhanced O-vacancies, which improve the transport of oxide ions. The present work shows that Sr0.7Co0.3FeO3−δ is a promising electrolyte for LT-SOFCs. Its performance can be boosted with Co-doping to tune the energy band structure.
Funding Information: This work was supported by Southeast University (SEU) PROJET no. 3203002003A1 and the National Natural Science Foundation of China (NSFC) under grant no. 51772080 and 11604088. Jiangsu Provincial Innovation and Entrepreneurship Talent Program Project No. JSSCRC2021491. Industry-University-Research Cooperation Project of Jiangsu Province in China, Grant No. BY2021057. Dr Asghar thanks the Hubei Talent 100 program and Academy of Finland (Grant No. 13329016, 13322738) for their financial support. Publisher Copyright: © 2022 The Royal Society of Chemistry.
Other note
Lu, Y, Yousaf Shah, M A K, Mushtaq, N, Yousaf, M, Lund, P D, Zhu, B & Asghar, M I 2022, ' A-site deficient semiconductor electrolyte Sr 1−x Co x FeO 3−δ for low-temperature (450-550 °C) solid oxide fuel cells ', RSC Advances, vol. 12, no. 38, pp. 24480-24490 . https://doi.org/10.1039/d2ra03823d