Nanoengineering of a Commercial-Scale Cathode Undergoing Highly Active Oxygen Dissociation via a Synergistic Effect of Sm0.5Sr0.5CoO3/Ce0.8Sm0.2O2 Composite Catalyst Infiltration for High-Performance Solid Oxide Fuel Cells

Abstract

Unmatched superior electrochemical performance and remarkable robustness of large-area (100 cm²) La_0.6Sr_0.4Co_0.2Fe_0.8O_3–δ-Ce_0.9Gd_0.1O_2−δ (LSCF-GDC) composite cathodes, optimized via a surface modification method with a Sm_0.5Sr_0.5CoO_3–δ/Ce_0.8Sm_0.2O_2−δ (SSC-SDC) nanocatalyst, are reported in this study. A well-dispersed network of SSC and SDC composite nanoparticles adorns a porous LSCF-GDC backbone, fostering the ORR kinetics of indigenous cathodes and showing substantially enhanced electrochemical performance. SOFC cathodes are upgraded with dissimilar amounts of SSC-SDC composite nanoparticles during single and double cycles of infiltration, showing corresponding powers of 46.48 and 53.16 W at 700 °C and a 60 A applied current, representing a breakthrough in performance for commercial-sized SOFCs. Moreover, the SOFCs demonstrate exceptional durability for up to 1500 h of galvanostatic operation under a 30 A applied current at an operating temperature of 700 °C due to the effect of the composite cathode catalyst material, which inhibits nanoparticle coarsening. This study provides a pragmatic approach for realizing the potential of nanocomposite infiltration to ameliorate the surfaces of SOFC cathode materials to promote commercialization of current SOFC technologies.