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Updated: Jul 2, 2026
07:50
Hydrogen Charging of Aluminum using Friction in Water
Published on: January 28, 2020
First-principles theory of hydrogen diffusion in aluminum
Hakan Gunaydin1, Sergey V Barabash, K N Houk
1Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.
Physical Review Letters
|September 4, 2008
Summary
Ab initio molecular dynamics simulations reveal hydrogen diffusion in aluminum. Vacancies significantly impact diffusivity by binding hydrogen, leading to composition-dependent, non-Arrhenius behavior.
Area of Science:
- Materials Science
- Computational Physics
- Physical Chemistry
Background:
- Lattice diffusion of hydrogen in aluminum is crucial for understanding material properties.
- Previous studies may not fully capture the complex interactions between hydrogen and vacancies.
Purpose of the Study:
- To determine the activation enthalpy and preexponential factor for hydrogen lattice diffusion in aluminum.
- To investigate the influence of vacancies on hydrogen diffusion behavior.
Main Methods:
- Utilizing ab initio molecular dynamics simulations.
- Performing simulations within the temperature range of 650 to 850 K.
Main Results:
- Calculated activation enthalpy (ΔH‡) as 0.12 ± 0.02 eV.
- Determined the preexponential factor (D0) as 1.8 x 10⁻⁷ m²/s.
- Observed that vacancies significantly decrease apparent diffusivity due to hydrogen binding.
Conclusions:
- Hydrogen diffusion in aluminum exhibits strong composition dependence.
- The presence of vacancies leads to non-Arrhenius behavior in the effective diffusion coefficient.
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