Unique porous thick Sm0.5Sr0.5CoO3 solid oxide fuel cell cathode films prepared by spray pyrolysis

Ultrasonic spray pyrolysis assisted by an electrostatic field was used to deposit thick Sm0.5Sr0.5CoO3 (SSC) films (> 40 mu m) as solid oxide fuel cell (SOFC) cathodes with a unique porous columnar structure. The high porosity and great thickness provided many active sites for reduction reaction. The space between columnar, as well as the large pores (similar to 100nm) inside the columns allowed gas molecules to diffuse quickly to the reaction sites; thus, very low interfacial resistance values (0.20 and 0.035 Omega cm(2) at 600 and 700 degrees C, respectively) were obtained. Moreover, the high deposition rate, ease of operation in open air and low cost make the ultrasonic spray pyrolysis assisted by an electrostatic field a particularly useful method for preparation of films ideal for SOFC operation. (c) 2008 Elsevier B.V. All rights reserved.