Pulsed Laser Deposition of Sm0.2Ce0.8O1.9/Zr0.9Sc0.1O2 Bilayer Films for Fuel Cell Application
Samarium doped ceria exhibits relative high conductivity of 0.1 S/cm at 700 °C and has been considered to be an attractive electrolyte for solid oxide fuel cells operating at the temperature range between 500 to 600 °C. Although the material exhibits better chemical and structural compatibility with electrodes as well as higher ionic conductivity than Yttria-stabilized Zirconia, the reduction of Ce4+ to Ce3+ induces n-type electronic conduction which tends to decrease power output of solid oxide fuel cells. The problem can be eliminated by using a barrier of thin Zr0.9Sc0.1O2 layer deposited over SDC layer as an alternative electrolyte to improve the stability of Samarium doped ceria under reducing atmosphere. In this work, we will report the results on the development of the Pulsed Laser Deposition (PLD) process to fabricate Sm0.2Ce0.8O1.9/Zr0.9Sc0.1O2 bilayer films. Bilayer films with controlled microstructures, density, and interfacial properties were successfully grown by the PLD at various deposition temperatures on Si(100) substartes. X-ray diffraction was used to determine their crystal structures, while the cross section images of the film-film and film-substrate interfaces were examined by field-emission SEM. The film density was calculated from the index of reflection data determined by a fiber-optic spectrophotometer.
T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran
D. F. Yang, "Pulsed Laser Deposition of Sm0.2Ce0.8O1.9/Zr0.9Sc0.1O2 Bilayer Films for Fuel Cell Application", Materials Science Forum, Vols. 539-543, pp. 1344-1349, 2007