Microstructure and Electrochemical Characterization of Sm0.5Sr0.5CoO3 Films as SOFC Cathode Prepared by the Electrostatic-Assisted Ultrasonic Spray Pyrolysis Method

Sm0.5Sr0.5CoO3 cathode films for solid oxide fuel cells were deposited on Ce0.9Gd0.1O1.95 disks using the electrostatic-assisted spray pyrolysis method. While an increase of deposition temperature resulted in enhanced evaporation and diminished wetting of aerosol droplets on substrates and led to more porous films, an increase of electrostatic field strength resulted in more extensive wetting and denser films. Films of a unique porous columnar structure were obtained using a deposition temperature of 400 degrees C, an applied voltage of 10 kV, and extended deposition times up to 600 s, rendering a minimum interfacial area specific resistance of 0.035 Omega.cm(2) at 700 degrees C in air.