First principles density functional theory study of tritium species adsorption on Ni(111) surface and diffusion in nickel-sublayer for tritium storage.

The nickel-plated zircaloy-4 is used as a tritium (H) getter in the tritium-producing burnable absorber rods (TPBARs) to capture H produced in the Li-riched annular γ-LiAlO pellet under neutron irradiation. The experimental data and our previous theoretical results showed that the H species produced from the γ-LiAlO pellet were mainly H and HO. These H species diffuse from the surface of the LiAlO pellet across vacuum to the nickel-plated zircaloy-4 getter and then further diffuse into the getter to chemically form metal hydrides.

Molecular dynamics simulations of displacement cascades in LiAlO and LiAlO ceramics.

Molecular dynamics was employed to investigate the radiation damage due to collision cascades in LiAlO and LiAlO, the latter being a secondary phase formed in the former during irradiation. Atomic displacement cascades were simulated by initiating primary knock-on atoms (PKA) with energy values = 5, 10 and 15 keV and the damage was quantified by the number of Frenkel pairs formed for each species: Li, Al and O. The primary challenges of modeling an ionic system with and without a core-shell model for oxygen atoms were addressed and new findings on the radiation resistance of these ceramics are presented.

Influence of ambient gas on self-reversal in Li transitions relevant to isotopic analysis.

Laser induced breakdown spectroscopy is a promising, rapid analysis method for the detection and quantification of Li and its isotopes needed in geochemical, nuclear, and energy storage applications. However, spectral broadening in laser produced plasmas, presence of fine and hyperfine structures, and self-reversal effects make Li isotopic analysis via laser induced breakdown spectroscopy challenging. The present study explores the influence of Ar, N, and He ambient gases over the pressure range of 0.

Probing the Radial Chemistry of Getter Components in Light Water Reactors via Controlled Electrochemical Dissolution.

Getters are among the key functional components in the tritium-producing burnable absorber rods (TPBARs) of light water reactors (LWRs) and are used to capture the released tritium gas. They are nickel-plated zircaloy-4 tubes that, upon exposure to irradiation or tritium in the light water reactors, undergo alteration in structure, chemical composition, and chemistry. Understanding the radial tritium distribution is key to gaining insight into the evolution of new chemistry upon irradiation to predict getter performance.

An electrochemical technique for controlled dissolution of zirconium based components of light water reactors.

Zircaloy-4 (Zr-4) based liners and getters are the principle functional components of Tritium-Producing Burnable Absorber Rods (TPBARs) in light water nuclear reactors where they reduce tritiated water into tritium gas. Upon tritium exposure, zirconium tritide is formed, which changes the chemical composition, structure and morphology of these materials. Their thermodynamic properties are affected by (i) the hydride phase identity, (ii) radial and spatial tritide/hydride (T/H) distribution, and (iii) the changes in structure and morphology of the material upon T/H-migration, and their comprehensive knowledge is needed to predict performance of these materials.