Preparation and Performance of Sm1-Ca CrO3-δ as New Interconnect Materials for IT-SOFC

Abstract

Abstract Sm1-xCaxCrO3-δ (x=0, 0.1, 0.2, 0.3, 0.4) as new interconnecting materials for solid oxide fuel cells (SOFCs) were developed. The ceramic powders with nominal compositions of Sm1-xCaxCrO3-δ were prepared via a citric acid method. Results show that the powders exhibit a good sintering ability, and the Ca-doped samples are denser than the undoped (SmCrO3) after sintering at 1400 °C for 5 h in air. The average thermal expansion coefficients (TECs) of the Sm1-xCaxCrO3-δ specimens in the temperature range of 30∼1000 °C increase from 7.34×10−6 to 8.05×10−6 K−1 when x increases from 0.1 to 0.4, which well match with those of other components of SOFC. The electrical conductivity of Sm0.7Ca0.3CrO3-δ is 29.8 S·cm−1 at 700 °C in air and 1.68 S·cm−1 at 600 °C in H2. It suggests that Sm0.7Ca0.3CrO3-δ is a good candidate for interconnect material of SOFCs.