Optimization of misfit calcium cobaltite oxygen electrodes for solid oxide fuel cells through electrospinning processing

verfasst von
Allan J.M. Araújo, Itzhak I. Maor, Laura I.V. Holz, Meirav Mann-Lahav, Vadim Beilin, Armin Feldhoff, Gideon S. Grader, Francisco J.A. Loureiro
Abstract

Current research in oxygen electrodes for Solid Oxide Fuel Cell applications underscores that the commercialization process of this technology remains severely limited by the poor oxygen reduction reaction performance of cathode materials. The misfit calcium cobalt oxide [Ca2CoO3−δ]0.62[CoO2] (CCO) presents a promising prospect in this regard, boasting fast surface-exchange kinetics coupled to a thermal expansion coefficient closely aligned with that of standard electrolytes. Nevertheless, its polarization losses are limited by a poor bulk oxygen-ion conduction, which confines the oxygen diffusion to a surface pathway, where the microstructure plays a significant role. Therefore, this study explores an alternative processing route for the synthesis of CCO via the electrospinning technique, resulting in a microstructure composed of small platelet-like grains with increased surface area, as well as enhanced grain-to-grain connectivity. Our work comprehensively assesses the particular benefits of electrospinning, where both the fiber breakage during the electrode preparation and the higher aspect ratio of the synthesized particles play a key role in the final electrode microstructure. This modification significantly enhances the electrochemical processes of the CCO electrode prepared by this route, resulting in a reduction of the total polarization resistance between 60% and 69% in the temperature range (800 to 600) °C, compared to a sample produced by the state-of-the-art solid-state reaction. Overall, our work highlights electrospinning as a promising alternative methodology for fabricating CCO cathodes with superior electrochemical performance.

Organisationseinheit(en)
Institut für Physikalische Chemie und Elektrochemie
Externe Organisation(en)
University of Aveiro
LASI - Intelligent Systems Associate Laboratory
Technion-Israel Institute of Technology
Typ
Artikel
Journal
Journal of Materials Chemistry A
Band
12
Seiten
26266-26279
Anzahl der Seiten
14
ISSN
2050-7488
Publikationsdatum
2024
Publikationsstatus
Veröffentlicht
Peer-reviewed
Ja
ASJC Scopus Sachgebiete
Allgemeine Chemie, Erneuerbare Energien, Nachhaltigkeit und Umwelt, Allgemeine Materialwissenschaften
Ziele für nachhaltige Entwicklung
SDG 7 – Erschwingliche und saubere Energie
Elektronische Version(en)
https://doi.org/10.1039/d4ta04085f (Zugang: Geschlossen)