Performances of YBaCo1.4Cu0.6O5+δ-Ce0.8Sm0.2O1.9 composite cathodes for intermediate-temperature solid oxide fuel cells

The electrochemical properties of YBaCo1.4Cu0.6O5+delta-xCe(0.8)Sm(0.2)O(1.9) (YBCC-xSDC, x=20, 30, 40, 50 wt%) have been investigated for the potential application in intermediate-temperature solid oxide fuel cells (IT-SOFCs). No chemical reactions between YBCC cathode and SDC electrolyte, and YBCC and La0.9Sr0.1Ga0.8Mg0.2O3-delta (LSOM) occur. The thermal expansion coefficient (TEC) of YBCC cathode decreases with SDC addition. The IEC of YBCC-30SDC cathode is 13.60 x 10(-6) K-1 from 30 to 850 degrees C in air and it exhibits the best electrochemical performance among the YBCC-xSDC cathodes. The polarization resistance (R-p) of YBCC-30SDC is 0.027 Omega cm(2) at 850 degrees C, 0.044 Omega cm(2) at 800 degrees C and 0.075 Omega cm(2) at 750 degrees C. The maximum power density value of electrolyte-based cell with YBCC-30SDC cathode is 662, 483 and 319 mW cm(-2) at 850, 800 and 750 degrees C, respectively. Preliminary results indicate that YBCC-30SDC is especially promising as a cathode for IT-SOFCs. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.