CO/CO2 Study of High Performance La0.3Sr0.7Fe0.7Cr0.3O3–δ Reversible SOFC Electrodes1. Issue 5 (21st September 2015)

• Record Type: Journal Article
• Authors: Addo, P. K.; Molero‐Sanchez, B.; Chen, M.; Paulson, S.; Birss, V.; Christiansen, Niels; Hagen, Anke; Bele, Petra; Bucheli, Olivier
• Is Part Of: Fuel cells. Volume 15:Issue 5(2015)
• Page Start: 689
• Page End: 696
• Publication Date: 2015-09-21
• Subjects: Fuel cells -- Periodicals; 621.312429
• DOI: 10.1002/fuce.201400196
• Languages: English
• ISSNs: 1615-6846

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>In this study, we demonstrate that the La<sub>0.3</sub>Sr<sub>0.7</sub>Fe<sub>0.7</sub>Cr<sub>0.3</sub>O<sub>3–</sub><italic><sub>δ</sub></italic> (LSFCr) perovskite, examined here as a CO/CO<sub>2</sub> fuel electrode material intended for symmetrical, reversible solid oxide fuel cell (RSOFC) applications, is both high performing and stable towards CO<sub>2</sub> electrolysis (SOEC mode) and the oxidation of CO (SOFC mode). To demonstrate this, symmetrical LSFCr/GDC/YSZ/GDC/LSFCr cells were evaluated electrochemically by using both DC (cyclic voltammetry (CV) and galvanostatic) and AC (impedance) techniques. The cells were tested at 800 °C using either 90% CO<sub>2</sub>:10% CO or 70% CO<sub>2</sub>:30% CO at the fuel electrode and air flowing to the O<sub>2</sub> electrode. From the open circuit impedance data, the polarization resistance, measured at 800 °C in a 90% CO<sub>2</sub>:10% CO and 70% CO<sub>2</sub>:30% CO gas composition, was 1.3 Ω cm<sup>2</sup> and 0.9 Ω cm<sup>2</sup>, respectively. Both the CV and polarized impedance data showed that the cell performance is higher during the electrolysis of CO<sub>2</sub> than for the oxidation of CO. Furthermore, the cell showed a very stable activity during CO<sub>2</sub> electrolysis, with a degradation rate of only 0.057 mV h<sup>−1</sup> after ca. 135 h of galvanostatic testing at –100 mA cm<sup>−2</sup> in 90% CO<sub>2</sub>:10% CO at 800 °C. </p> </abstract>