Correlation between annihilation of radiation defects and tritium release in Li2TiO3

Thermal annihilation kinetics of radiation defects and thermal release of tritium produced in neutron-irradiated Li2TiO3 were studied by ESR and a thermal desorption method, respectively. Annealing experiments indicated that there were two annihilation processes of the radiation defects, the fast and the slow processes, and their activation energies were determined to be 0.43 and 0.41 eV, respectively. Taking account of the previous studies on Li2O and Li4SiO4, it is suggested that the fast process is related to Li+ diffusion, and the slow process is attributed to annihilation of oxygen vacancies. The comparison of the defects annihilation and tritium release shows that the slow process and the tritium release from bulk appear simultaneously. Hence, the annihilation of oxygen vacancy in each sample, or in any other CBMs, could play an important role in tritium release processes.