A critical review of experiments on deuterium retention in displacement-damaged tungsten as function of damaging dose

Abstract

Experimental results from the literature on the evolution of deuterium retention in displacement-damaged tungsten as a function of damaging dose are presented. Except for a few outliers, retention is generally found to increase with the presence of displacement damage. However, total retention results scatter by three orders of magnitude for similar exposure temperatures and are difficult to compare, because they depend on experiment-specific parameters such as the irradiation energy used to produce the displacement damage or the deuterium exposure parameters such as fluence. Even local deuterium concentration measurements were found to scatter by more than one order of magnitude. An experimental methodology is proposed that allows robust conclusions about the evolution of deuterium retention with damage dose and the results are discussed in detail. Recrystallized tungsten is irradiated with 20.3 MeV self-ions at room temperature with different damage doses ranging from 0.001 to 2.3 displacements per atom. The defects are then decorated with a low flux, low-energy deuterium plasma at 450 K sample temperature. 3He Nuclear Reaction Analysis (NRA) shows that the deuterium concentration levels off from the linear increase already at very low damage dose of about 0.005 dpa. At a damage dose of 0.23 dpa a maximum deuterium concentration of about 1.4 at% is reached. Thermal Desorption Spectroscopy (TDS) shows that with damage increasing above 0.005 dpa, the overall shape of the desorption spectra does not change substantially, only their intensities increase. Total amounts derived from TDS are in quantitative agreement with results from 3He-NRA. Experimental results following this methodology also agree quantitatively with very recent parameter-free modeling of damage evolution.

Deuterium retention in co-deposition with lithium in Magnum-PSI: experimental analysis and comparison with SOLPS-ITER

“…There is little literature regarding Li-D co-depositions in a D plasma environment and with in-situ diagnostics. Tabares et al [16] exposed tungsten plates to lithium-seeded deuterium plasma at temperatures between 130 • C-600 • C. The measured Li and D content were below the NRA detection limit, for all but one case, at 130 • C. In this case the D/Li ratio was less than 10 −4 , which is similar to retention rates of D in W at this temperature [17]. Krat et al [18] conducted magnetron sputtering with D 2 onto a Li target, capturing both D and Li on a molybdenum substrate.…”

Modelling neutron damage effects on tritium transport in tungsten

“…Data from the work of Pec ˇovnik et al [11] has been used to evaluate the annealing parameters (A 0 and E A ). To evaluate the damaging parameters (K and n max,Φ ), unpublished data from T. Schwarz-Selinger was used that was generated following the procedure outlined in [31].…”

Comparative Passivation of Si(100) by H2 and D2 Atmospheres under Simultaneous Xe+ Bombardment: An X-ray Photoelectron Spectroscopy Analysis

“…11,12 Furthermore, the research on the retention of hydrogen and isotopes on the surface holds significant potential for nuclear fusion energy. 13,14 Tokamak reactors commonly employ hydrogen and isotopes as fuel sources, and the interaction of these species in the plasma state on the inner walls of the reactor has garnered significant attention in current studies. 15−18 Moreover, hydrogen storage assisted by plasma has garnered attention from several research groups.…”

“…H 2 and D 2 are commonly applied to passivate Si substrates in the microelectronic industry to prevent contamination, such as H 2 O, which is present in the base pressure of standard vacuum vessels. − Additionally, passivation finds various applications in thin film technologies, serving as anticorrosive protection and interface functionalization and creating hard coatings. − Passivation of dangling bonds is crucial in hydrogenated amorphous silicon materials. , Furthermore, the research on the retention of hydrogen and isotopes on the surface holds significant potential for nuclear fusion energy. , Tokamak reactors commonly employ hydrogen and isotopes as fuel sources, and the interaction of these species in the plasma state on the inner walls of the reactor has garnered significant attention in current studies. − Moreover, hydrogen storage assisted by plasma has garnered attention from several research groups. , To control the physical–chemical mechanisms of passivation, factors like the surface state, temperature, and sticking coefficient must be taken into consideration. − …”