Journalartikel

Jahr der Veröffentlichung: 2016

Seiten: 10486-10491

Zeitschrift: Physical Chemistry Chemical Physics

Bandnummer: 18

Heftnummer: 15

ISSN: 1463-9076

eISSN: 1463-9084

Open Access Status: Hybrid

DOI Link: https://doi.org/10.1039/c5cp08032k

Verlag: Royal Society of Chemistry

Abstract: 
In recent years, interface engineering of solid electrolytes has been explored to increase their ionic conductivity and improve the performance of solid oxide fuel cells and other electrochemical power sources. It has been observed that the ionic conductivity of epitaxially grown thin films of some electrolytes is dramatically enhanced, which is often attributed to effects (e.g. strain-induced mobility changes) at the heterophase boundary with the substrate. Still largely unexplored is the possibility of manipulation of grain boundary resistivity in polycrystalline solid electrolyte films, clearly a limiting factor in their ionic conductivity. Here we report that the ionic conductivity of yttria stabilized zirconia thin films with nano-columnar grains grown on a MgO substrate nearly reaches that of the corresponding single crystal when the thickness of the films becomes less than roughly 8 nm (smaller by a factor of three at 500 degrees C). Using impedance spectroscopy, the grain boundary resistivity was probed as a function of film thickness. The resistivity of the grain boundaries near the film-substrate interface and film surface (within 4 nm of each) was almost entirely eliminated. This minimization of grain boundary resistivity is attributed to Mg2+ diffusion from the MgO substrate into the YSZ grain boundaries, which is supported by time of flight secondary ion mass spectroscopy measurements. We suggest grain boundary "design'' as an attractive method to obtain highly conductive solid electrolyte thin films.

Harvard-Zitierstil: Mills, E., Kleine-Boymann, M., Janek, J., Yang, H., Browning, N., Takamura, Y., et al. (2016) YSZ thin films with minimized grain boundary resistivity, Physical Chemistry Chemical Physics, 18(15), pp. 10486-10491. https://doi.org/10.1039/c5cp08032k

APA-Zitierstil: Mills, E., Kleine-Boymann, M., Janek, J., Yang, H., Browning, N., Takamura, Y., & Kim, S. (2016). YSZ thin films with minimized grain boundary resistivity. Physical Chemistry Chemical Physics. 18(15), 10486-10491. https://doi.org/10.1039/c5cp08032k