Tritium Accommodation and Diffusion in LiPbO from First-Principles Simulations.

LiPbO has been proposed as an alternative candidate breeding blanket material for use in fusion reactors. As lithium is burned inside the blanket, tritium is produced within the ceramic matrix until it reaches the surface, from where it is recovered by isotope exchange reactions. To fully understand the tritium recovery process, it is essential to understand how tritium is accommodated in the fuel and subsequently migrates to the surface.

High-Temperature Intrinsic Defect Chemistry of LiPbO Ceramic Breeding Material.

Understanding the intrinsic defect chemistry of tritium breeder materials proposed for use in future fusion reactors is imperative, as certain defects may act as traps leading to retention of tritium in the ceramic matrix. In this paper, we use combined density functional theory simulations with simple thermodynamics to explore the intrinsic defect chemistry of octalithium plumbate (LiPbO) as a function of both temperature and oxygen partial pressure. Importantly, we consider vibrational contributions to the energies of the reference states used in the calculations of the defect formation energies.

Thermodynamics and phase stability of LiOoctalithium ceramic breeder materials (= Pb, Ce, Ge, Zr, Sn).

Octalithium ceramics with their high stoichiometric concentration of lithium offer exceptionally high tritium breeding ratios in comparison with other candidate breeder materials for tokamak fusion reactors, this is especially true with incorporation of a neutron multiplier into the crystal structures. Although, there are concerns surrounding the stability of these materials at operational temperatures. Therefore in this paper, we explore the thermodynamic properties of a selection of candidate octalithium ceramics in low and high temperature regimes (0-1200 K) using density functional perturbation theory.