Oxygen Reduction Response of La and Ce Co-Doped SrCoO_3−δ Perovskite Oxide Grown on Porous Ni-Foam Substrate

Abstract

Lately, ceramic fuel cells (CFCs) have held exceptional promise for joint small- and large-scale applications. However, the low-oxygen reduction response of cathode materials has hindered the low operating temperature of CFCs. Herein, we have developed a semiconductor based on La and Ce co-doped SrCoO3 and embedded them in porous Ni-foam to study their electrochemical properties. The porous Ni-foam-pasted La0.2Sr0.8Co0.8Ce0.2O3‒δ cathode displays small-area-specific resistance and excellent ORR (oxygen reduction reaction) activity at low operating temperatures (LT) of 450–500 °C. The proposed device has delivered an impressive fuel cell performance of 440 mW-cm−2, using La0.2Sr0.8Co0.8Ce0.2O3−δ embedded on porous Ni-foam substrate cathode operation at 550 °C with H2 fuel and atmospheric air. It even can function well at a lower temperature of 450 °C. Moreover, La0.2Sr0.8Co0.8Ce0.2O3−δ embedded on porous Ni-foam shows very good activation energy compared to individual SrCoO3 and La0.1Sr0.9Co0.9Ce0.1O3−δ embedded on porous Ni-foam, which help to promote ORR activity. Different characterization has been deployed, likewise: X-ray diffraction, photoelectron-spectroscopy, and electrochemical impedance spectroscopy for a better understanding of improved ORR electrocatalytic activity of prepared La0.2Sr0.8Co0.8Ce0.2O3−δ embedded on porous Ni-foam substrate. These results can further help to develop functional cobalt-free electrocatalysts for LT-SOFCs.

Keywords

• La_0.2Sr_0.8Co_0.8Ce_0.2O_3−δ
• La and Ce co-doped
• porous Ni-foam substrate
• electrochemical properties
• spectroscopic studies
• LT-SOFCs cathode