No 1, Vol. 6, 2004, pages 7-11


U. Brossmann1, G. Knöner2, H.-E. Schaefer2 and R. Würschum1

1 Institute of Technical Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
2 Institute of Theoretical and Applied Physics, University of Stuttgart, D-70550 Stuttgart, Germany


Stabilized ZrO2×Y2O3 represents one of the most promising materials for technical applications as a solid electrolyte in sensors and fuel cells, since it combines a high ionic conductivity of oxygen with mechanical and chemical resilience. The question, whether the oxygen conductivity can be further enhanced by nanostructurization, is of key importance for the development of solid oxide fuel cells (SOFC), as lower operating temperatures greatly improve the efficiency and working lifespan. The oxygen self-diffusion has been studied on highly dense, nanocrystalline specimens of both un-doped and Y2O3 alloyed ZrO2 using 18O as a tracer and secondary ion mass spectroscopy (SIMS). The results of tracer diffusion studies will be discussed in context of recent studies on the electric conductivity and diffusion data from literature and focusing on the role of grain boundaries.

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