Pr6O11 as an Excellent Oxygen Catalyst Enhances the Electrocatalytic Activity of Ruddlesden-Popper Perovskite for SOFC Composite Cathodes

Ruddlesden-Popper phase perovskites, a class of traditional SOFC cathode materials, are limited by inadequate ORR activity under intermediate temperatures. This research proposes fabricating composite cathodes by blending La 2 Ni 0.9 Sc 0.1 O 4+δ (LNSO) with Pr 6 O 11 (PO), which is a promising oxygen catalyst, at varying concentrations.The impacts of composite electrodes on the material’s thermal stability, electrochemical performance, and structural properties were explored using XRD, FE-SEM, and an electrochemical workstation. Experimental results demonstrate that 30% PO content notably boosts the surface oxygen content of the cathode material and improves its ORR catalytic activity. Relaxation time distribution results indicate that LNSO-30PO speeds up the oxygen adsorption and dissociation processes. At 700 °C, the symmetric cell with LNSO-30PO as the electrode exhibits a polarization resistance as low as 0.063 Ω·cm 2 , representing a 51.5% decrease relative to pure LNSO. When integrated into a single-cell SOFC as the cathode, LNSO-30PO enables the device to reach a PPD of 0.96 W cm -2 (1.28 times that of the LNSO-based counterpart) while maintaining excellent long-term stability. These findings suggest that LNSO-30PO is a viable candidate for IT-SOFC cathodes.