Studies of lithiumization and boronization of ATJ graphite PFCs in NSTX-U

This work examines the effect of boron and lithium conditioned ATJ graphite surface bombarded by low-energy deuterium atoms on the deuterium retention and chemical sputtering. We use atomistic simulations and compare them with experimental in situ studies with x-ray photoelectron spectroscopy (XPS),...

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Bibliographic Details
Main Authors: F.J. Domínguez-Gutiérrez, F. Bedoya, P.S. Krstic, J.P. Allain, A.L. Neff, K. Luitjohan
Format: Article
Language:English
Published: Elsevier 2017-08-01
Series:Nuclear Materials and Energy
Online Access:http://www.sciencedirect.com/science/article/pii/S235217911630223X
Description
Summary:This work examines the effect of boron and lithium conditioned ATJ graphite surface bombarded by low-energy deuterium atoms on the deuterium retention and chemical sputtering. We use atomistic simulations and compare them with experimental in situ studies with x-ray photoelectron spectroscopy (XPS), to understand the effects of deuterium irradiation on the chemistry in lithiated, boronized and oxidized amorphous carbon surfaces. Our results are validated qualitatively by comparison with experiments and with quantum classical molecular dynamic simulations. We explain the important role of oxygen in D retention for lithiated surfaces and the suppression of oxygen role by boron in boronized surfaces. The calculated increase of the oxygen role in deuterium uptake after D accumulation in BCO surface configuration is discussed. The sputtering yield per low energy D impact is significantly smaller in boronized than in lithiated surfaces. Keywords: Plasma-surface interactions, Deuterium retention, NSTX, Boronization, Lithiumization, Carbon
ISSN:2352-1791