Characterization of La0.8Sr0.2MnO3 +/-delta Nanopowders Synthesized by Aerosol Flame Synthesis for SOFC Cathode

Abstract

Lanthanum strontium manganite (La0.8Sr0.2MnO3 +/-delta, LSM) powders with a high specific surface area (55.26 m(2)/g) were successfully synthesized by aerosol flame synthesis (AFS) technique. The crystallinity and morphology of the synthesized powders sintered at various temperatures were studied by XRD, TEM and BET. The synthesized powders exhibited spherical shape mostly in a few nanometer ranges with a relatively high crystallinity due to thermal plasma reactions in a high temperature of oxy-hydrogen flame. To analyze electrochemical performances of synthesized LSM powders, impedance spectroscopy (IS) was carried out with the symmetric cells prepared by slurry based electrostatic spray deposition (ESD) onto the YSZ electrolyte pellet. The interfacial polarization resistances were 3.04 Omega.cm(2) at 750 degrees C which is relatively lower than that of micro-porous film (7.24 Omega.cm(2)) applying micro-sized powders deposited on same condition.