A novel cobalt-free layered GdBaFe2O5+δ cathode for proton conducting solid oxide fuel cells

• Published in: Journal of power sources 2010-07, Vol.195 (13), p.4139-4142
• Main Authors: Ding, Hanping, Xue, Xingjian
• Format: Article
• Language: English
• Subjects: 30 DIRECT ENERGY CONVERSION; Applied sciences; carbon sequestration; catalysis (heterogeneous), energy storage (including batteries and capacitors); charge transport; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; hydrogen and fuel cells; materials and chemistry by design; mechanical behavior; membrane; synthesis (novel materials); synthesis (scalable processing); synthesis (self-assembly)
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2010.02.006

While cobalt-containing perovskite-type cathode materials facilitate the activation of oxygen reduction, they also suffer from problems like poor chemical stability in CO2 and high thermal expansion coefficients. In this research, a cobalt-free layered GdBaFe2O5+δ (GBF) perovskite was developed as a cathode material for protonic ceramic membrane fuel cells (PCMFCs) based on proton conducting electrolyte of stable BaZr0.1Ce0.7Y0.2O3-δ (BZCY7). The button cells of Ni–BZCY7|BZCY7|GBF were fabricated and characterized using complex impedance technique from 600 to 700 °C. An open-circuit potential of 1.007 V, maximum power density of 417 mW cm-2, and a low electrode polarization resistance of 0.18 Ω cm2 were achieved at 700 °C. The results indicate that layered GBF perovskite is a good candidate for cobalt-free cathode material, while the developed Ni–BZCY7|BZCY7|GBF cell is a promising functional material system for solid oxide fuel cells.