Impurity influence on the hydrogen diffusivity in B2-TiFe

The projector augmented-wave method within the electron density functional theory is used for calculations of the hydrogen absorption energy and its migration barriers in the doped B2-TiFe. An analytical expression for the temperature-dependent diffusion coefficients of the hydrogen in the doped alloy is derived using Landman's method. An approach for estimation of the average jump rates of hydrogen that are necessary for calculations of the diffusion coefficient in the doped alloys is developed. The activation energy of hydrogen diffusion and the pre-exponential factor are estimated. The effect of impurities on the hydrogen diffusion in the alloy is discussed. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

The projector augmented-wave method based on electron density functional theory is used to calculate the absorption energy and migration barriers of hydrogen in doped B2-TiFe. An analytical expression for the temperature-dependent diffusion coefficients of hydrogen in the doped alloy is derived using Landman's method. An approach to estimate the average jump rates of hydrogen for calculating the diffusion coefficient in doped alloys is developed. The effect of impurities on hydrogen diffusion in the alloy is discussed.