Solid oxide fuel cells (SOFCs) offer the advantages of high efficiency, low pollution emission, and low processing cost. SOFC quality is strongly influenced by the preparation process. Composite La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) samarium-doped ceria carbonate (SDCC) cathode for low-temperature SOFCs was developed, and the effect of sintering soaking time on the physical properties of an LSCF–SDCC composite cathode was studied. Composite cathode powders with 50 wt.% LSCF and 50 wt.% SDCC were mixed before undergoing calcination and uniaxial pressing process. The pressed samples were sintered at 600 °C and soaked at 1, 2, and 3 hr. The porosity and density results obtained by the Archimedes method showed a decrement of porosity from 24.92% to 19.62% and an increment of density from 4.03 g cm−1 to 4.15 g cm−1 under 1 hr to 3 hr of soaking time. Scanning electron microscopy reveals that the grain size of the composite cathode surface increases with increasing soaking time. X-ray diffraction results demonstrate that the diffraction angles at 33o and 59o exhibit a decreasing SDCC peak because of the increasing grain size. However, the new peak of lithium chromium oxide (Li2CrO4) appears at an angle of 21.66° for 3 hr soaking time. The findings proved that soaking time influences the microstructure of the composite cathode.
Fabrication of Electrolyte for Low-temperature SOFC by Electrophoretic Deposition of Ceramic Fine Powders
