Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5147985 | International Journal of Hydrogen Energy | 2017 | 7 Pages |
Abstract
To acquire knowledge of the effect of chromium dopant bringing on hydrogen diffusion along grain boundaries (GBs) of α-Al2O3, the energetics and mobility of hydrogen along Σ13 GB with and without Cr dopant have been studied via the first-principles calculations with the projector-augmented wave method. The energy barriers for hydrogen diffusion before and after Cr doped on Al-terminated Σ13 GB are determined to be 0.69 eV and 1.09 eV, respectively, which is smaller than or close to the hydrogen bulk diffusion with an activation energy of 1.10 eV. The results suggest that before doping Cr atoms, there is a rapid and easy diffusion channel for hydrogen along the Σ13 GB. However, the calculations show the segregation of Cr atoms to the GB is energetic favorable with a segregation energy of â0.39 eV/atom, and the existence of Cr can suppress hydrogen diffusion along the Al-terminated Σ13 GB.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Ying Dong, Fei Wang, Wensheng Lai,