First-principles study of hydrogen diffusion in transition metal palladium

Abstract

By adopting the first-principles total energy calculations based on density functional theory (DFT), the diffuse pattern and path of hydrogen in bulk palladium are investigated by calculating the system energy of hydrogen atom occupying different positions in palladium crystal lattice. The results indicate that the most stable position of hydrogen atom in palladium crystal lattice locates at the octahedral interstice, and the tetrahedral interstice is the second stable site. Hydrogen diffusion along the indirect octahedral–tetrahedral–octahedral (O–T–O) path is energetically most favorable in transition metal palladium, and the activation energy is 0.5245 eV.