Low temperature sintering ability and electrical conductivity of SOFC interconnect material La0.7Ca0.3Cr0.97O3

Abstract

Relatively low temperature (1150–1300 °C) sintering characteristics and electric conductivities of La 0.7 Ca 0.3 Cr 0.97 O 3 with a slight Cr deficiency of 0.03, prepared by an auto-ignition process, have been discussed. The material could reach 94.3% relative density at 1200 °C for 5 h in air, which is about 200 °C lower than that of with no Cr deficiency. XRD results indicated that pure perovskite phase was formed after sintered at the temperature range of 1150–1300 °C. The sample sintered at 1250 °C had the maximum conductivity of 62.0 S cm −1 at 850 °C in air, which is about 2.6 times as high as that of La 0.7 Ca 0.3 CrO 3 with no Cr deficiency. In pure H 2 , it got the maximum electrical conductivity of 3.3 S cm −1 at 850 °C as sintered at 1200 °C. The TEC of the material was about 11.4 × 10 −6 K −1 , which is very compatible to that of other common used SOFC components. Therefore, it is a simple and cost-effective interconnect material for SOFCs.