Journal of the American Ceramic Society, Vol.84, No.11, 2573-2578, 2001
Thermal expansion behavior of titanium-doped La(Sr)CrO3 solid oxide fuel cell interconnects
La0.8Sr0.2Cr0.9Ti0.1O3 perovskite has been designed as an interconnect material in high-temperature solid oxide fuel cells (SOFCs) because of its thermal expansion compatibility in both oxidizing and reducing atmospheres. La0.8Sr0.2Cr0.9Ti0.1O3 shows a single phase with a hexagonal unit cell of a = 5.459(1)Angstrom, c = 13.507(2) Angstrom, Z = 6 and a space group of R-3C. Average linear thermal expansion coefficients of this material in the temperature range from 50 degrees to 1000 degreesC were 10.4 x 10(-6)/degreesC in air, 10.5 x 10(-6)/degreesC under a He-H-2 atmosphere (oxygen partial pressure of 4 x 10(-15) atm at 1000 degreesC), and 10.9 x 10(-6)/degreesC in a H-2 atmosphere (oxygen partial pressure of 4 x 10(-19) atm at 1000 degreesC). La0.8Sr0.2Cr0.9Ti0.1O3 perovskite with a linear thermal expansion in both oxidizing and reducing environments is a promising candidate material for an SOFC interconnect. However, there still remains an air-sintering problem to be solved in using this material as an SOFC interconnect.