Fabrication and conductivity of zirconium doped Li2TiO3 tritium breeder

Abstract

The tritium diffusion rate of the tritium breeder is one of the main factors affecting the Deuterium–Tritium (DT) nuclear fusion. In the paper, the zirconium ion (Zr4+)-doped Li2TiO3 tritium breeder with a small grain size of 0.66 μm was successfully prepared at a high temperature of 950 °C. Zr4+-doping could inhibit grain growth of Li2TiO3, which benefited from the effect of segregating, pinning, and dragging to the Li2TiO3 grain boundary. Then, the conductivity was innovatively used to indirectly and rapidly evaluate the tritium release property of Zr4+-doped Li2TiO3. The results show that the short lithium-ion diffusion distance for the small-grained Zr4+-doped Li2TiO3 decreases bulk resistance, and the abundant interfaces enhance grain boundary conductivity. Besides, the zirconium (Zr) dopant increases the cell volume of Li2TiO3, which provides a broader channel for the diffusion of lithium ion. It indirectly illustrates that the Zr4+-doped Li2TiO3 with small grains has better tritium release performance than the Li2TiO3 with large grains. The results would provide new insights into the Zr doping to accelerate tritium diffusion on the Li2TiO3 surface.