Effects of temperature and surface contamination on D retention in ultrathin Li films on TZM
Abstract
In this work, we investigate deuterium retention at the Mo-Li interface by studying thin Li films three monolayers thick on a TZM Mo alloy. Li films at temperatures between 315 and 460 K were exposed to a deuterium ion beam and D retention was measured using temperature programmed desorption. In the absence of oxygen, D is retained as LiD, and the relative amount of retained D decreases with increasing substrate temperature. In three-monolayer thick lithium oxide films, the amount of D retained was 2.5 times higher than the amount retained as LiD in the metallic Li film. However, oxygen reduces the thermal stability of D in the film, causing D2O and D2 to be released from the surface at temperatures 150-200 K below the LiD decomposition temperature. These results highlight the importance of maintaining a metallic Li layer for high D retention in Li films on TZM at elevated temperatures.
- Publication:
-
Journal of Nuclear Materials
- Pub Date:
- August 2015
- DOI:
- 10.1016/j.jnucmat.2014.10.048
- Bibcode:
- 2015JNuM..463.1177C