Journal
JOURNAL OF PHYSICS-CONDENSED MATTER
Volume 31, Issue 25, Pages -Publisher
IOP PUBLISHING LTD
DOI: 10.1088/1361-648x/ab0f6b
Keywords
first principles; density functional theory; hydrogen; tungsten; surface; adsorption; migration
Categories
Funding
- Fusion Energy Sciences (FES) program
- Advanced Scientific Computing Research (ASCR) program
- FES within the U.S. Department of Energy Office of Science [DE-SC-0006661]
- U.S. Department of Energy [DE-AC02-05CH111231, DE-AC05-00OR22725]
- US Department of Energy through the Los Alamos National Laboratory
- National Nuclear Security Administration of U.S. Department of Energy [89233218CNA000001]
Ask authors/readers for more resources
We report on density functional theory calculations that have been performed to systematically investigate the hydrogen-surface interaction as a function of surface orientation. The interactions that were analyzed include stable atomic adsorption sites, molecular hydrogen dissociation and absorption energies, migration pathways and barriers on tungsten surfaces, and the saturation coverage limits on the (111) surface. Stable hydrogen adsorption sites were found for all surfaces. For the reconstructed W(100), there are two primary adsorption sites: namely, the long-bridge and short-bridge sites. The threefold hollow site (3F) was found to be the most stable for W(110), while the bond-centered site between the first and second layer was found to be most stable for the W(1 1 1) surface. No bound adsorption sites for H-2 molecules were found for the W surfaces. Hydrogen (H) migration on both the (100) and (110) surfaces is found to have preferred pathways for 1D motion, whereas the smallest migration barrier for net migration of H on the W(111) surface leads to 2D migration. Although weaker H interactions are predicted for the W(111) surface compared to the (100) or (110) surfaces, we observe higher H surface concentrations of circle minus = 4.0 at zero K, possibly due to the corrugated surface structure. These results provide insight into II adsorption, surface saturation coverage and migration mechanisms necessary to describe the evolution from the dilute limit to concentrated coverages of H.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available