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Solid oxide cells (SOCs) have important applications as fuel cells and electrolyzers. The application for storage of renewable electricity is also becoming increasingly relevant; however, it is difficult to meet stringent area-specific resistance (ASR) and long-term stability targets needed to achieve required efficiency and cost. Here we show a new SOC that utilizes a very thin Gd-doped ceria (GDC)/yttria-stabilized zirconia (YSZ) bi-layer electrolyte, Ni–YSZ cell support with enhanced porosity, and electrode surface modification using PrO x and GDC nanocatalysts to achieve unprecedented low ASR values < 0.1 Ω cm 2 , fuel cell power density ∼3 W cm −2 , and electrolysis current density ∼4 A cm −2 at 800 °C. Besides this exceptionally high performance, fuel cell and electrolysis life tests suggest very promising stability in fuel cell and steam electrolysis modes. Electrochemical impedance spectroscopy analysis done using a novel impedance subtraction method shows how rate-limiting electrode processes are impacted by the new SOC materials and design.
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How an angstrom-thick oxide overcoat enhances durability and activity of nanoparticle-decorated cathodes in solid oxide fuel cells
In this report, we demonstrate that a uniform angstrom-level oxide overcoat (either ceria or yttria with a nominal thickness of 0.7–1.5 Å) by atomic layer deposition is highly effective not only in enhancing the thermal stability of underlying infiltrated ceria nanoparticles but also in facilitating electrode kinetics. By employing Sr-free electrodes and Cr-free gas environment, we focus on the thermal agglomeration as the major degradation pathway and reveal the close correlation between thermal agglomeration rate of infiltrated nanoparticles and degradation rate of electrode performance in a quantitative manner. We also provide a mechanistic perspective on the beneficial effect of the overcoat in durability and performance of solid oxide fuel cell cathodes.
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- Award ID(s):
- 1753383
- PAR ID:
- 10223388
- Date Published:
- Journal Name:
- Journal of Materials Chemistry A
- Volume:
- 8
- Issue:
- 31
- ISSN:
- 2050-7488
- Page Range / eLocation ID:
- 15927 to 15935
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D0TA02915G
