Fabrication and characterization of La0.65Sr0.3MnO3−δ/(Y2O3)0.08(ZrO2)0.92/Gd0.1Ce0.9O2−δ tri-composite cathode-supported tubular direct carbon solid oxide fuel cell

The purpose of this study was to fabricate a porous supporting cathode for direct carbon solid oxide fuel cells (DCFC). Therefore, the effect of Gd0.1Ce0.9O2−δ (GDC) addition on the phase stability, sintering behavior, thermal expansion, and porosity of La0.65Sr0.3MnO3−δ/(Y2O3)0.08(ZrO2)0.92 (LSM/YSZ) composite was evaluated. The sintering temperature and the porosity of the LSM/YSZ composite were observed to increase with increase in the amount of GDC. An LSM/YSZ/GDC tri-composite with optimized properties was selected to fabricate the tubular cathode-supported DCFCs (LSM/YSZ/GDC|YSZ|NiO/YSZ) through extrusion, slurry coating, and co-firing. A special chamber was designed for the DCFC operation of the tubular cell. Electrochemical characterization was performed by measuring the polarization curves and electrochemical impedance spectroscopy, using the syngas produced by in situ steam gasification of carbon black.