Evaluation of simple, easily sintered La0.7Ca0.3Cr0.97 O3-δ perovskite oxide as novel interconnect material for solid oxide fuel cells

Simple, easily sintered perovskite oxide as a novel interconnect material for solid oxide fuel cells (SOFCs) was evaluated at a SOFC co-firing temperature (1400 degrees C). Chemical compatibility, sintering character, electrical conductivity and thermal expansion were investigated to characterize the compatibilities of La0.7Ca0.3Cr0.97O3-delta (LCC97) with Y0.16Zr0.84O2-delta (YSZ), NiO, Sm0.2Ce0.8O2-delta (SDC), La0.8Sr0.2MnO3-delta (LSM), and BaZr0.1Ce0.7Y0.2O3-delta (BZCY), respectively The XRD analysis indicates LCC97 chemically incompatible with BZCY. The mixtures of LCC97/SDC and LCC97/NiO, respectively, exhibit high relative densities of 97.6% and 96.2% after sintering at 1400 degrees C for 5 h in air. However, the samples of LCC97/YSZ and LCC97/LSM only have poor sintering abilities. The samples of LCC97 mixed with LSM, SDC, NiO and YSZ, respectively, have a decreasing electrical conductivity of 24.0 S cm(-1), 12.2 S cm(-1), 7.8 S cm(-1) and 0.17 S cm(-1) at 850 degrees C in air, which are all much lower than that of the LCC97 sample (62.0 S cm(-1)). Different mixing slightly increases the TEC value of LCC97. Results indicate that, under SOFC co-firing conditions, the novel interconnect material LCC97 has desired compatibilities with SDC and NiO, while it displays poor compatibilities with YSZ and LSM. (C) 2009 Elsevier B.V. All rights reserved.