Effects of pre-calcined YSZ powders at different temperatures on Ni-YSZ anodes for SOFC

The particle size distribution and the specific surface area of yttria stabilized zirconia (YSZ) powders could be changed by pre-calcining. Accordingly, the performances of Ni-YSZ cermet might be changed too. In this paper, the effects of pre-calcined YSZ powders on Ni-YSZ cermet were investigated. The performances of Ni-YSZ cermet, including the basic physical characterization, sintering shrinkage and electrochemical properties, were studied in connection with the quality of YSZ powders pre-calcined at 900 degrees C, 1100 degrees C and 1200 degrees C, respectively. The results indicated that the crystal structure was not changed, but the porosity of open holes in NiO-YSZ pellets was increased with the pre-calcining temperature increasing. In addition, the total shrinkage of different anode materials was changed by using different YSZ powders, the value of Ni-YSZ cermet doping with YSZ pre-calcined at 900 degrees C and 1100 degrees C was closer to that of YSZ electrolyte. The cermet with YSZ powders pre-calcined at 900 degrees C showed the highest electric conductivity, and its polarization performance was closed to that of cermet with raw YSZ powders. (c) 2005 Elsevier B.V. All rights reserved.