Effects of lead addition on tritium recovery for advanced Li2TiO3-Li4SiO4 mixed breeder material

The effect of Pb addition on tritium recovery for Li ₂TiO ₃-Li ₄SiO ₄ mixed ceramic materials was investigated by Tritium-thermal desorption spectroscopy (T-TDS). The behavior of irradiation defects was also studied by electron spin resonance (ESR) with heating. The sample with the lower neutron fluence of 8.0 × 10 ¹⁵ n cm ⁻² had a tritium desorption stage on the low temperature side, 400 K, which can be ascribed to the tritium adsorption on the surface. As the neutron fluence was increased, the desorption of tritium retained in the bulk was major tritium desorption process. The major desorption stage was shifted to the lower temperature side by Pb addition. The intensity of ESR peak corresponding to O ⁻-center was reduced by Pb addition, indicating the irradiation defect was decreased. This contributes on the reduction of tritium trapping sites and facilitates tritium recovery on the lower temperature side.