YSZ/Al 2 O 3 multilayer thick films deposited by spin coating using ceramic suspensions on Al 2 O 3 polycrystalline substrate

Abstract Yttria Stabilized Zirconia (YSZ) high chemical and thermomechanical stability under Solid Oxide Fuel Cells (SOFCs) standard operational conditions and its high electrolytic domain indicate that an interesting alternative for lowering SOFCs operating temperature would be the development of high conductive YSZ-based electrolytes compared to conventional electrolytes through microstructure engineering. In this work, YSZ/Al 2 O 3 micrometric multilayer films obtained by spin coating presented electrical conductivity 3.5 times higher than traditional YSZ ceramics. The multilayer film was formed by three layers of YSZ with 3.7 µm of thickness each were intercalated by two 7.4 µm thick layers of Al 2 O 3 . Therefore, the high electrical conductivity observed in nanometric multilayer films obtained by advanced techniques was achieved, even with lower magnitude, with ceramic suspensions and in the micrometric scale. Computer simulation shows higher stresses on YSZ than on Al 2 O 3 layers, correlating the heterofilms higher conductivity with the stress imposed on the YSZ layer during sintering.