SrCo0.85Fe0.15O2.62 – Oxygen Deficient "314‐type" Perovskite; a Highly Efficient Cathode for Solid Oxide Fuel Cells. Issue 3 (9th June 2017)

• Record Type: Journal Article
• Authors: Marik, S.; Nicollet, C.; Channabasappa, M.; Fourcade, S.; Wattiaux, A.; Duttine, M.; Decourt, R.; Bassat, J.‐M.; Toulemonde, O.
• Is Part Of: Fuel cells. Volume 17:Issue 3(2017:Jun.)
• Page Start: 353
• Page End: 358
• Publication Date: 2017-06-09
• Subjects: Cathode -- Cobaltate -- Solid Oxide Fuel cell -- 314‐type Structure; Fuel cells -- Periodicals; 621.312429
• DOI: 10.1002/fuce.201600203
• Languages: English
• ISSNs: 1615-6846

Abstract

Abstract: Structure, electrical conductivity and electrochemical performance for a new oxygen deficient perovskite material with composition SrCo0.85 Fe0.15 O2.62 is explored here. It crystallizes in a "314‐type" oxygen‐vacancy ordered structure (Space Group: I 4 /mmm ) with 2ap × 2ap × 4ap unit cell, and contains alternate oxygen replete [Co2/Fe2‐O] and oxygen deficient [Co1/Fe1‐O] planes along c‐direction. Room temperature Mössbauer spectroscopy and room temperature neutron powder diffraction confirm the presence of mixed valence states (3+ and 4+) for both Fe and Co. Polaronic behavior in the electrical conductivity is observed below 400 °C, and attributed to the presence of Co 4+ and Fe 3+ cations in the structure. The electrical conductivity at 600 °C is high enough (∼200 S cm −1 ) to act as a cathode material. At the same time, the polarization resistance measurements show an excellent value of 0.1 Ω cm 2 at 600 °C. These results suggest that at 600 °C, this material is a mixed oxide‐ion and electronic conductor exhibiting excellent activity for the oxygen reduction reaction, making it a promising cathode material for an intermediate temperature solid oxide fuel cell.