Nitrogen diffusion in nitrogen-doped yttria stabilised zirconia
Nitrogen self-diffusion was measured in single crystalline nitrogen-doped yttria-stabilised zirconia (YZrON) containing 10 mol% yttrium oxide. Samples containing two different nitrogen contents (5 and 6 mol% N on the anion sublattice) were investigated as a function of temperature (650–1000 K) using...
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| Autores principales: | , , , , , , |
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| Formato: | Articulo |
| Lenguaje: | Inglés |
| Publicado: |
2004
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| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/97644 https://ri.conicet.gov.ar/11336/74366 https://pubs.rsc.org/en/Content/ArticleLanding/2004/CP/B315123A#!divAbstract |
| Aporte de: |
| Sumario: | Nitrogen self-diffusion was measured in single crystalline nitrogen-doped yttria-stabilised zirconia (YZrON) containing 10 mol% yttrium oxide. Samples containing two different nitrogen contents (5 and 6 mol% N on the anion sublattice) were investigated as a function of temperature (650–1000 K) using implanted <sup>15</sup>N as a stable tracer. For a given temperature, the nitrogen diffusivity was nearly independent of the nitrogen content in the nitrogen-doped yttria-stabilised zirconia, which can be only partially understood using defect chemistry. The activation enthalpy of nitrogen diffusion was between 2 and 2.5 eV with a preexponential factor of the order of 10<sup>0</sup> cm<sup>2</sup> s<sup>−1</sup>, which corresponds to a migration entropy of 5 k<sub>B</sub>. The surface exchange reaction between nitrogen and the oxonitride surface was investigated at 1073 K using 200 mbar gaseous <sup>15</sup>N<sub>2</sub> and was found to be slow but considerable. Decreasing the oxygen content in the gas phase can enhance the nitrogen incorporation into the oxonitrides. |
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