You are here

Anisotropic Diffusion of a Charged Tritium Interstitial in Li2TiO3 from First-Principles Calculations

TitleAnisotropic Diffusion of a Charged Tritium Interstitial in Li2TiO3 from First-Principles Calculations
Publication TypeJournal Article
Year of Publication2018
AuthorsShi, YL, Qi, JQ, Han, Y, Lu, TC
JournalPhysical Review Applied
Volume10
Pagination024021
Date Published08
Type of ArticleArticle
ISBN Number2331-7019
Accession NumberWOS:000441860900001
Keywordsceramic breeder materials, crystal, dynamics, elastic band method, kinetics, lithium titanate, minimum energy paths, occupation sites, physics, release behavior, saddle-points
Abstract

Tritium diffusion in the nuclear fusion reactor breeder material Li2TiO3 is a fundamentally important process for tritium-release kinetics. The energy barrier of tritium diffusion in Li2TiO3 has been reported with a considerable uncertainty in previous experiments. Here, we perform systematic density-functionaltheory (DFT) studies for the diffusion processes of positively charged tritium, which is the preferential charge state of the tritium interstitial in a single Li2TiO3 crystal. By calculating various local-diffusion minimum-energy paths, we find that the diffusion of tritium is strongly anisotropic along different crystalline directions. The most favorable diffusion paths appear within a Li-6 atomic single layer of Li2TiO3 and the corresponding DFT diffusion barrier is 0.334 eV, while the diffusion barrier for the most favorable diffusion paths crossing a Li2Ti4 atomic layer is 1.006 eV.

DOI10.1103/PhysRevApplied.10.024021
Custom 1

Surface Structures

Alternate JournalPhys. Rev. Appl.