C. Suciu, E. Dorolti, A.C. Hoffmann
University of Bergen, Norway
pp. 235 - 238
Keywords: nanoparticles, fuel cells, YSZ, characterization
Nanoparticles of oxides are used, among other things, for solid oxide fuel cells (SOFCs), where the use of yttria-stabilized zirconina nanoparticles in the inner region of the anode will increase the extent of the "triple-phase boundary" at which the electrochemical reaction can take place. Also using nano-particle precursors for the electrolyte offers new possibilities for designing the grainstructure. Analyses of a series of xYSZ materials, where x varies from 1-15%, have been carried out both in their nanopowder form and after sintering to functional materials, namely ion-conducting ceramics in the form of pellets. The following analyses have been carried out and are shown in the paper: BET, XRD, TEM, densities, linear shrinkage upon sintering and EIS data. XRD analyses show that the particles are in the cubic crystal structure. The analyses further show that all the interatomic distances increase with increasing doping. The relative densities of the sintered materials exhibit a minimum at 8% doping. In spite of this, EIS analyses show that the material resistivities were minimal at around 8% doping. The EIS data reveal the temperature-dependent impedance of the materials and the nature of the effect of the grainstructure on this.