Role of energetic tritium chemistry on developing thermonuclear fusion reactors

The reaction kinetics of the two conversion processes for the chemical state of tritium in neutron irradiated Li2O during the thermal annealing was investigated. The chemical states of tritium were T− state and T+ state. The abundance of T− state was increased in the temperature region of 400–500 K (Conversion I) and it was decreased above 500 K (Conversion II). These kinetic constants were determined. The kinetics of Conversion I and Conversion II was determined to be 7.79 exp(0.45 ± 0.04 eV/kT) s−1 and 8.53 × 104 exp(0.90 ± 0.08 eV/kT) s−1, respectively. The annealing kinetics of irradiation defects of F-centers (oxygen vacancy occupied by one electron), which was a major defect in neutron-irradiated Li2O, was also studied. Based on those experimental results, a comprehensive migration model for energetic tritium produced in lithium oxides including the dynamics of irradiation defects was proposed.