Effect of Synthesis Conditions on the Performance of Cu ­ CeO2 ­ YSZ Anodes in SOFCs

Abstract

The effect that synthesis procedures have on the performance of (yttria-stabilized zirconia) anodes for solid oxide fuel cells (SOFC) has been investigated. Using a fixed concentration of 20 wt % Cu and 10 wt % impregnated into a porous YSZ matrix using metal salts, it is shown that the methods used to prepare and Cu have a large effect on the cell performance. Direct reduction of to Cu, without intermediate calcination to results in Cu films that have better electrical connectivity, but this does not enhance the final cell performance after exposure to n-butane. The calcination temperature for preparing from has a much more significant effect, with the area-specific resistance (ASR) of the anode in at 973 K increasing from 0.8 Ω cm2 at 723 K to >1.8 Ω cm2 at 1273 K and >2.6 Ω cm2 at 1523 K. X-ray diffraction results indicate that most of the ceria has not formed a solid solution, even at 1523 K. The cell performance is also affected by the solvent used for impregnation of Forming the film with in ethanol resulted in a cell with an anode ASR of ∼0.4 Ω cm2. Possible reasons for the strong dependence of the ceria film on cell performance are discussed. © 2003 The Electrochemical Society. All rights reserved.