Co-synthesized (La0.8Sr0.2)0.9MnO3Y0.15Zr0.85O2 composite for solid oxide fuel cell cathode

(La0.8Sr0.2)0.9MnO3Y0.15Zr0.85O2 (LSM-YSZ) composite co-synthesized by citrate-nitrate combustion method are investigated for solid oxide fuel cell cathode. The co-synthesized LSM-YSZ composite powders are characterized by XRD, HR-SEM, TEM, HR-TEM and EDX analysis. The phase separation of the precursor into LSM perovskite and YSZ fluorite occurs at temperatures above 900 °C, about 200 °C higher than the formation temperature of pure LSM or pure YSZ. In the nano-sheets of LSM-YSZ composite, nano-particles of LSM and YSZ are well distributed and intimately contacted with each other. The nanostructures remain in the co-synthesized LSM-YSZ cathode. The co-synthesized LSM-YSZ cathode improves oxygen reduction reaction (ORR) activity, especially at reduced operation temperature. The cell with co-synthesized LSM-YSZ cathode delivers current density 150% times of the cell with traditional LSM-YSZ cathode at 600 °C. Electrochemical impedance spectra (EIS) analysis shows that oxygen reduction reaction is accelerated due to high three phase boundary (TPB) density. The co-synthesized LSM-YSZ cathode shows good stability under cell operation at 800 °C.