Oxygen Tracer Diffusion in Lanthanum-Doped Single-Crystal Strontium Titanate |
| |
| Authors: | Uta Kiessling,Jü rgen Claus,Gü nter Borchardt,Sylvain Weber,Stanislas Scherrer |
| |
| Affiliation: | AG Elektronische Materialtcn, SFB180, Technischc Universitαt Clausthal, D-38678 Clausthal-Zelletfeld, Germany;Laboratoire de Métallurgie Physique-Sciences des Matériaux, Ecole des Mines de Nancy, F-54042 Nancy Cedex, France |
| |
| Abstract: | Strontium titanate (SrTiO3) is known as a good high-temperature resistive oxygen sensor material; its response time depends on oxygen bulk diffusion and surface exchange processes. In the present work, 18O diffusion has been investigated in lanthanum-doped SrTiO3, single crystals in the temperature range 700° to 900°C by secondary ion mass spectrometry (SIMS). Oxygen tracer diffusivities between 2 × 10−15 and 1 × 10−13 cm2/s have been calculated from the SIMS results. Low surface enrichment of 18O compared to the 18O concentration in the gas atmosphere gives clear evidence for a surface exchange reaction. |
| |
| Keywords: | |
|
|
