Release kinetics of tritium generation in neutron irradiated biphasic Li2TiO3-Li4SiO4 ceramic breeder

Biphasic Li2TiO3-Li4SiO4 tritium breeders with different phase ratios were prepared by the solution combustion synthesis method. The as-prepared biphasic Li2TiO3-Li4SiO4 and single-phase materials were irradiated by the thermal neutron with the flux of 2.75 x 10(13) n cm(-2) s(-1) at Kyoto University Research Reactor (KUR). Tritium is generated based on the following reaction: Li-6+(1)n -> T-3+He-4+4.8 MeV. The results of tritium release experiment show that tritium release starts at the lower temperature range for the biphasic materials. The tritium release temperature and the shape of tritium-TDS (Thermal desorption spectroscopy) spectra are dependent on the phase ratio of Li2TiO3 to Li4SiO4. In the case of Li2TiO3/Li4SiO4 = 2.0, tritium release starts at 400 K, and the tritium migration is mainly controlled by the diffusion process. With the increase of Li4SiO4 content in the biphasic materials, tritium release is influenced by the de-trapping process. (C) 2019 Elsevier B.V. All rights reserved.