Electrochemical performance of Sm0.5Sr0.5Co1.1-xFexO3-δ (x=0, 0.02, 0.05, 0.08, 0.1) cathodes for intermediate temperature solid oxide fuel cells

The development of cathodes that operate efficiently at low and medium temperatures is critical to advancing solid oxide fuel cells (SOFCs). Sm0.5Sr0.5Co1.1O3-δ (SSC1.1) cathodes are highly regarded for their superior catalytic properties. In this study, we investigate the influence of Fe doping - a common modification in cobalt-based perovskites on the performance of SSC1.1. A series of Sm0.5Sr0.5Co1.1-xFexO3-δ (SSC1.1-xFx, x = 0, 0.02, 0.05, 0.08, 0.1) materials are synthesized by substituting different amounts of Fe for Co at the B-site. Our results show that Fe doping generally reduces the catalytic performance of SSC1.1, except for the SSC1.05F0.05 compositions. The SSC1.05F0.05 cathode exhibits a polarization resistance of 0.293 Ω cm2 at 650 °C, comparable to the 0.275 Ω cm2 observed for the undoped SSC1.1. In addition, an anode supported single cell using SSC1.05F0.05 as the cathode achieves a peak power density of 0.532 W cm−2 at 700 °C, exceeding that of several conventional cathode materials. This study highlights the potential of SSC1.05F0.05 as a promising cathode material for intermediate-temperature SOFCs. © 2025 Hydrogen Energy Publications LLC