Lithium wall conditioning in TFTR, CDX-U, T-11M, TJ-II and NSTX is found to yield enhanced plasma performance manifest, in part, through improved deuterium particle control. X-ray photoelectron spectroscopy (XPS) experiments examine the affect of D irradiation on lithiated graphite and show that the surface chemistry of lithiated graphite after D ion bombardment (500 eV/amu) is fundamentally different from that of non-Li conditioned graphite. Instead of simple LiD bonding seen in pure liquid Li, graphite introduces additional complexities. XPS spectra show that Li-O-D (533.0 ± 0.6 eV) and Li-C-D (291.4 ± 0.6 eV) bonds, for a nominal Li dose of 2 μm, become "saturated" with D at fluences between 3.8 and 5.2 × 10 17 cm-2. Atomistic modeling indicate that Li-O-D-C interactions may be a result of multibody effects as opposed to molecular bonding.
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Materials Science(all)
- Nuclear Energy and Engineering