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Abstract A traditional composite cathode for proton‐conducting solid oxide fuel cells (H‐SOFCs) is typically obtained by mixing cathode materials and proton conducting electrolyte of BaCe0.7Y0.2Zr0.1O3–δ(BZCY), providing chemical and thermal compatibility with the electrolyte. Here, a series of triple‐conducing and cobalt‐free iron‐based perovskites as cathodes for H‐SOFCs is reported. Specifically, BaCexFe1–xO3–δ(x = 0.36, 0.43, and 0.50) shows various contents of two single phase perovskites with an in situ heterojunction structure as well as triple conductivity by tailoring the Ce/Fe ratios. The cell performance with the optimized BaCe0.36Fe0.64O3–δ(BCF36) cathode composition reaches 1056 mW cm−2at 700 °C. Moreover, a record cell performance of 1525 mW cm−2at 700 °C is obtained by modifying the BCF36 cathode microstructure through a spraying method, demonstrating high promise with Co‐free cathodes for H‐SOFCs.
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Progress in proton‐conducting oxides as electrolytes for low‐temperature solid oxide fuel cells: From materials to devices
Abstract Among various types of alternative energy devices, solid oxide fuel cells (SOFCs) operating at low temperatures (300‐600°C) show the advantages for both stationary and mobile electricity production. Proton‐conducting oxides as electrolyte materials play a critical role in the low‐temperature SOFCs (LT‐SOFCs). This review summarizes progress in proton‐conducting solid oxide electrolytes for LT‐SOFCs from materials to devices, with emphases on (1) strategies that have been proposed to tune the structures and properties of proton‐conducting oxides and ceramics, (2) techniques that have been employed for improving the performance of the protonic ceramic‐based SOFCs (known as PCFCs), and (3) challenges and opportunities in the development of proton‐conducting electrolyte‐based PCFCs.
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- Award ID(s):
- 1661699
- PAR ID:
- 10386763
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Energy Science & Engineering
- Volume:
- 9
- Issue:
- 7
- ISSN:
- 2050-0505
- Format(s):
- Medium: X Size: p. 984-1011
- Size(s):
- p. 984-1011
- Sponsoring Org:
- National Science Foundation
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