Dependency of irradiation damage density on tritium migration behaviors in Li sub(2)TiO sub(3)

• Published in: Journal of nuclear materials Vol. 447; no. 1-3; pp. 1 - 8
• Main Authors: Kobayashi, Makoto, Toda, Kensuke, Oya, Yasuhisa, Okuno, Kenji
• Format: Journal Article
• Language: English
• Published: 01.04.2014
• Subjects: Damage; Density; Fluence; Lithium; Migration; Oxygen atoms; Radiation damage; Tritium
• ISSN: 0022-3115
• DOI: 10.1016/j.jnucmat.2013.12.001

Tritium migration behaviors in Li sub(2)TiO sub(3) with the increase of irradiation damage density were investigated by means of electron spin resonance and thermal desorption spectroscopy. The irradiation damages of F super(*)-centers and O super(-)-centers were formed by neutron irradiation, and their damage densities were increased with increasing neutron fluence. Tritium release temperature was clearly shifted toward higher temperature side with increasing neutron fluence, i.e. increasing damage density. The rate determining process for tritium release was also clearly changed depending on the damage density. Tritium release was mainly controlled by tritium diffusion process in crystalline grain of Li sub(2)TiO sub(3) at lower neutron fluence. The efficiency of tritium trapping/detrapping by the dangling oxygen atoms was clearly increased with increasing damage density due to the stabilization of damages by neighboring irradiation damages and/or the lithium bum-up which produces lithium vacancy acting as a pass way of tritium to the dangling oxygen atoms.