Comparative Characterization on Structural Properties of Calcined Sm0.5Sr0.5CoO3−δ - Sm0.2Ce0.8O1.9 Carbonate as Potential Composite Cathode for SOFC

In this research work, Samarium Strontium Cobalt Oxide, Sm0.5Sr0.5CoO3−δ (SSC) and Samarium Doped Ceria, Sm0.2Ce0.8O1.9 (SDC) carbonate or (SDCc) were used as the new composite cathode powder materials. This composite cathode powder was prepared via high energy ball milling (HEBM) method for SOFC application. The composition of 50 wt.% of SSC was chosen to be added with 50 wt.% of SDCc powder. The prepared powders of composite cathode SSC:SDCc were then undergone calcination process at different operating temperatures which has been varied from 600 °C, 650 °C, 700 °C and 750 °C. Characterizations of the SSC-SDCC composite cathode powders were performed through X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). However from the XRD analysis, there was an appearance of new secondary peaks which corresponded to strontium carbonate (strontianite), SrCO3 of SSC-SDCc composite cathode powders. The result obtained from FTIR analysis verified the existence of carbonates elements in all SSC-SDCc composite cathodes. Based on FTIR studies, the selection for operating temperatures of calcination did not give significant impact on the thermal and structural properties of calcined SSC-SDCc carbonate composite cathodes. Additionally, the presence of secondary phase revealed from the XRD study might result in different microstructural that could influence the electrochemical behavior. (paper)