Enhancing oxygen reduction activity of perovskite cathode decorated with core@shell nano catalysts

Highly active catalysts towards oxygen reduction reaction (ORR) with good stability are critical for reduced temperature solid oxide fuel cells (SOFCs). Nano Ag@M0.2Ce0.8O2-δ (M = La, Sm, Pr) catalyst with core@shell structure is in-situ synthesized via a facile hydrothermal method on porous La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) scaffold as SOFC cathode. The diameter of the silver core is ∼60 nm with a uniform outer shell ∼20 nm in thickness. A dramatic decrease (∼80% at 550 °C) on the interfacial polarization resistance was observed for this catalyst-decorated cathode compared to the pristine one. The durability test demonstrated a relatively stable operation for Ag@Pr0.2Ce0.8O2-δ decorated LSCF cathode. The excellent electrochemical performance of this hybrid electrode with convenient fabrication process presents a new strategy for rational design of SOFC cathode with excellent ORR activity and stability.