Ba- and La- Strontium Cobalt Ferrite Carbonate Composite as Cathode Materials for Low Temperature SOFC

Abstract

Barium strontium cobalt ferrite (BSCF) and lanthanum strontium carbonate ferrite (LSCF)–samarium-doped ceria carbonate (SDCc) composite cathodes were developed based on various molar ratio of binary carbonate. The percentage of molar ratio for (Li/Na)2 binary carbonate in the composite cathodes were 67:33, 62:38, and 53:47. Influence of (Li/Na)2 binary carbonate addition on BSCF-SDCc and LSCF-SDCc were studied in terms of chemical, thermal, and physical properties. The composite-cathode powders were prepared using high-energy ball milling (HEBM) and followed by calcination at 750 °C for 2h. Characterizations of the composite cathode were performed through Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and dilatometry. The FTIR result verified the existence of carbonates in all the composite cathodes. The increment in the Na2CO3 molar ratio has contributed to the growth of the BSCF-SDCc particles as observed from the FESEM micrographs and particle size. The LSCF-SDCc composite cathodes revealed a lower (1.38-6.69%) thermal coefficient difference with SDCc electrolyte. The BSCF-SDCc and LSCF-SDCc composites with 53:47 mol.% of (Li/Na)2 binary carbonate exhibit the applicable properties as SOFC cathode material.