Synthesis and characterization of scandia ceria stabilized zirconia powders prepared by polymeric precursor method for integration into anode-supported solid oxide fuel cells

摘要

Scandia ceria stabilized zirconia (lOSclCeSZ) powders are synthesized by polymeric precursor method for use as the electrolyte of anode-supported solid oxide fuel cell (SOFC). The synthesized powders are characterized in terms of crystalline structure, particle shape and size distribution by X-ray diffraction (XRD), transmission electron microscopy (TEM) and photon correlation spectroscopy (PCS). lOSclCeSZ electrolyte films are deposited on green anode substrate by screen-printing method. Effects of 10Scl CeSZ powder characteristics on sintered films are investigated regarding the integration process for application as the electrolytes in anode-supported SOFCs. It is found that the lOSclCeSZ films made from nano-sized powders with average size of 655 nm are very porous with many open pores. In comparison, the lOSclCeSZ films made from micron-sized powders with average size of 2.5 μm, which are obtained by calcination of nano-sized powders at higher temperatures, are much denser with a few closed pinholes. The cell performances are 911 mWcm~(-2) at the current density of 1.25 A cm~(-2) and 800℃ by application of Ce_(0.8)Gd_(0.2)O_2 (CGO) barrier layer and La_(0.6)Sr_(0.4)CoC_3 (LSC) cathode.