Highly electrocatalytic activity Ruddlesden_Popper type electrode materials for solid oxide fuel cells

To promote the viability of commercial solid oxide fuel cell (SOFC), developing novel oxygen electrodes with high electrochemical activity is essential. Herein, a series Ruddlesden-Popper oxides, Sr3_xLaxFe2O7_delta (SLFx), are successfully synthesized and evaluated as potential cathode materials for SOFC. The oxygen desorption behavior, electrochemical activity and oxygen reduction reaction (ORR) kinetics of the SLFx cathodes are systematically discussed. The Sr2.9La0.1Fe2O7_delta (SLF10) cathode exhibits highest oxygen vacancy concentration and excellent electrocatalytic performance, as evidenced by a low polarization resistance of 0.14 omega cm2 and high maximum power density of 0.77 W cm_ 2 at 700 degrees C. From electrochemical impedance spectra and distribution of relaxation times analysis, the oxygen adsorption/desorption process is the rate-limiting step toward ORR at the cathode interface. Furthermore, SLF10 shows considerable polarization overpotentials in both SOFC and solid oxide electrolysis cell (SOEC) modes, indicating that SLF10 is a promising bifunctional electrode for electrocatalytic oxygen reaction.

Automated summary

By synthesizing and evaluating Ruddlesden-Popper oxides as potential cathode materials for SOFC, it was found that SLF10 exhibits high oxygen vacancy concentration and excellent electrocatalytic performance, leading to a higher maximum power density for the fuel cell.