A Facile Combustion Synthesis Route for Performance Enhancement of La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF6428) as a Robust Cathode Material for IT-SOFC

Lanthanum-based transition metal cations containing perovskites have emerged as potential catalysts for the intermediatetemperature (600-800 o C) oxygen reduction reaction (ORR). Here, we report a facile acetylacetone-assisted combustion route for the synthesis of nanostructured La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3- (LSCF6428) cathodes for intermediate-temperature solid-oxide fuel cells (IT-SOFCs). The as-prepared powder was analyzed by thermogravimetry analysis-differential scanning calorimetry. The powder calcined at 800 o C was characterized by X-ray diffraction, scanning electrode microscopy, energy dispersive X-ray spectroscopy, and Brunauer-Emmett-Teller surface area measurements. It was found that the porosity of the air electrode significantly increased by utilizing the nanostructured LSCF6428 instead of commercial powder. The performance of a single cell fabricated with the nanostructured LSCF6428 cathode increased by 112%, from 0.4 to 0.85 W cm 2 , at 700 o C. Electrochemical impedance spectroscopy showed a considerable reduction in the area-specific resistance and activation energy from 133.5 to 61.5 kJ/mol, resulting in enhanced electrocatalytic activity toward ORR and overall cell performance.