Fabrication of Y2O3 Doped Zirconia/Gadolinia Doped Ceria Bilayer Electrolyte Thin Film SOFC Cells of SOFCs by Single Pulsed Laser Deposition Processing

Abstract

An 8 mol. % Y2O3doped zirconia/10mol. % GdO2doped ceria (YSZ/GDC) bilayer electrolyte and a Gd0.5Sr0.5CoO3 (GSCO) cathode were deposited by a singleprocessing, pulsed laser deposition (PLD) method to fabricate anode support cells. No additional heat treatment was needed. Laser frequencies of 10, 20, and 100 Hz were used to deposit bilayer electrolytes between the NiO–YSZ (NiO:YSZ = 60:40 wt. %) anode substrate and the GSCO cathode thin film. The GDC thin film produced at 10 Hz was smooth, wellcrystallized, and highly dense. The crystallinity of the GSCO cathode on the GDC was also improved. We concluded the GDC crystallinity affected the crystallinity of the cathode thin film. The resistivity of the YSZ single layer (5.7 خ¼m thickness) was 1.4 times higher than that of the YSZ/GDC bilayer (YSZ 3.0 خ¼m thickness, GDC 2.7 خ¼m thickness) at 600 آ°C and that of the YSZGDC interface became low. The optimum YSZ thickness was found to be approximately 3.0 خ¼m, at which thickness there was effective blocking of the passage of hydrogen molecules and electrons. A cell with a YSZ (3.0 خ¼m thickness, fabricated at 20 Hz)/GDC (5.0 خ¼m thickness, fabricated at 10 Hz) bilayer and GSCO cathode thin film exhibited a maximum power density of 400 mWآ·cm–2 at a comparatively low temperature of 600 آ°C.