Synthesis of Porous Particles of SOFC Anode and Cathode Materials by Citric Acid-Addition Ultrasonic Spray Pyrolysis (CA-USP)

Ultrasonic spray pyrolysis method to synthesize porous submicron particles of solid oxide fuel cell (SOFC) electrode materials was developed in which citric acid is added in a precursor solution. This citric acid-addition ultrasonic spray pyrolysis (CA-USP) method was then used to synthesize NiO-Gd0.1Ce0.9O1.95 (GDC) particles for SOFC anodes and La0.8Sr0.2Co3 (LSC) and La0.8Ca0.2MnO3 (LCM) particles for SOFC cathodes. The synthesized particles were submicron-sized, porous, and spherical, and had a sponge-like structure. Energy dispersive X-ray spectrometry images of the synthesized NiO-GDC particles revealed that Ni, Ce, Gd, and O were uniformly distributed within individual particles. NiO-GDC and LCM particles with sponge-like structure were not crushed by a 2-h ball mill grinding test. The formation process of the sponge-like structure was clarified by synthesizing GDC particles at various furnace temperatures between 473 and 1273 K.