Hydrogen isotope exchange via water exposure at oxyhydroxide surfaces of stainless steel and silicon

Conference · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6596941

Gill, J T; Watkins, D B; Schultz, J A; Anderson, L R; Schmidt, H K; Bastasz, R J

The rates at which hydrogen isotopes are exchanged on oxyhydroxide surface films of 304L stainless steel and Si(100) upon exposure to water vapor have been investigated. Surface films were prepared by bombardment with D/sub 2/0/sup +/. The surfaces were then monitored by SIMS and Direct Recoil Spectroscopy as a function of water (H/sub 2/0 or D/sub 2/O) exposure. A fast and a second much slower process characterize the exchange at both films. The processes are isotopically reversible. The fast process is limited by water exposure, complete in 5--10 L for both materials, and is considered to involve terminal hydroxyl groups. The slow process appears to be the bulk diffusion-limited exchange within the oxyhydroxide film. Exchange-diffusion constants have been derived from fits to TRIM calculations for depth-of-origin of sputtered species: D/sub ex/-10/sup -18/ and 10/sup -19/ cm/sup 2//sec for the films on 304LSS and Si, respectively, at 295K. These values are invariant (within a factor of 10) upon the choice of three widely different TRIM inputs. D/sub ex/ for 304LSS is consistent with previous results on FeOOH and SS. Diffusion exchange appears important in understanding tritium decontamination from surfaces. 47 refs., 8 figs.

• Research Organization: EG and G Mound Applied Technologies, Miamisburg, OH (USA)
• DOE Contract Number: AC04-88DP43495; AC04-76DP00789
• OSTI ID: 6596941
• Report Number(s): MLM-3552(OP); CONF-881002-27; ON: DE89003444
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400202* -- Isotope Effects
Isotope Exchange
& Isotope Separation
ALLOYS
CHROMIUM ALLOYS
CHROMIUM-NICKEL STEELS
DIFFUSION
ELEMENTS
FLUIDS
GASES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
HIGH ALLOY STEELS
HYDROGEN ISOTOPES
IRON ALLOYS
IRON BASE ALLOYS
ISOTOPES
ISOTOPIC EXCHANGE
KINETICS
MATERIALS
NICKEL ALLOYS
SEMIMETALS
SILICON
STAINLESS STEEL-304L
STAINLESS STEELS
STEEL-CR19NI10-L
STEELS
SURFACES
VAPORS
WATER VAPOR