skip to main content

DOE PAGESDOE PAGES

Title: Analysis of hydrogen adsorption and surface binding configuration on tungsten using direct recoil spectrometry

In our work, we apply low energy ion beam analysis to examine directly how the adsorbed hydrogen concentration and binding configuration on W(1 0 0) depend on temperature. We exposed the tungsten surface to fluxes of both atomic and molecular H and D. We then probed the H isotopes adsorbed along different crystal directions using 1–2 keV Ne+ ions. At saturation coverage, H occupies two-fold bridge sites on W(1 0 0) at 25 °C. Moreover, the H coverage dramatically changes the behavior of channeled ions, as does reconstruction of the surface W atoms. For the exposure conditions examined here, we find that surface sites remain populated with H until the surface temperature reaches 200 °C. Then, we observe H rapidly desorbing until only a residual concentration remains at 450 °C. Development of an efficient atomistic model that accurately reproduces the experimental ion energy spectra and azimuthal variation of recoiled H is underway.
Authors:
 [1] ;  [2] ;  [1] ;  [1] ;  [2]
  1. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
  2. Univ. of Tennessee, Knoxville, TN (United States)
Publication Date:
OSTI Identifier:
1145778
Report Number(s):
SAND--2014-4300J
Journal ID: ISSN 0022-3115; PII: S0022311514009222
Grant/Contract Number:
AC04-94AL85000
Type:
Accepted Manuscript
Journal Name:
Journal of Nuclear Materials
Additional Journal Information:
Journal Volume: 463; Journal Issue: C; Journal ID: ISSN 0022-3115
Publisher:
Elsevier
Research Org:
Sandia National Laboratories (SNL-CA), Livermore, CA (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS