A self-recovering robust electrode for highly efficient CO2 electrolysis in symmetrical solid oxide electrolysis cells†
Symmetrical solid oxide electrolysis cells (S-SOECs) have received increasing attention due to their low fabrication cost and simple preparation procedure. However, the investigation of S-SOECs for CO2 electrolysis has been hindered due to the lack of high performance stable electrodes with good CO2 reduction reaction (CO2-RR) and oxygen evolution reaction (OER) catalytic activity. Herein, a novel perovskite La0.6Ca0.4Fe0.8Ni0.2O3−δ (LCaFN) is investigated as an electrode of S-SOECs for CO2 electrolysis. The S-SOEC has a low polarization resistance of only 0.04 Ω cm2 and achieves a maximum electrolysis current density of 1.41 A cm−2 at 800 °C with pure CO2 at 2.0 V. LCaFN electrodes show good stability and can be recovered by simple air treatment after a period of operation to avoid the formation of carbonates with alkaline earth elements in the perovskite as La0.6Sr0.4Fe0.8Ni0.2O3−δ (LSrFN). The mechanism of self-recovery of the LCaFN electrode by air treatment is discussed and analyzed.
- This article is part of the themed collection: 2019 Journal of Materials Chemistry A HOT Papers