First-principles study of fission gas incorporation and migration in zirconium nitride

Journal Article · Fri Mar 24 04:00:00 EDT 2017 · Computational Materials Science

DOI:https://doi.org/10.1016/j.commatsci.2017.03.019· OSTI ID:1372349

Mei, Zhi-Gang ^[1]; Liang, Linyun ^[1]; Yacout, Abdellatif M. ^[1]

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1. Argonne National Lab. (ANL), Argonne, IL (United States)

To evaluate the effectiveness of ZrN as a diffusion barrier against fission gases, we investigate in this paper the incorporation and migration of fission gas atoms, with a focus on Xe, in ZrN by first-principles calculations. The formations of point defects in ZrN, including vacancies, interstitials, divacancies, Frenkel pairs, and Schottky defects, are first studied. Among all the defects, the Schottky defect with two vacancies as first nearest neighbor is predicted to be the most favorable incorporation site for fission gas Xe in ZrN. The migration of Xe gas atom in ZrN is investigated through two diffusion mechanisms, i.e., interstitial and vacancy-assisted diffusions. The migration barrier of Xe gas atom through the intrinsic interstitials in ZrN is considerably lower than that through vacancies. Finally, therefore, at low temperatures fission gas Xe atoms diffuse mainly through interstitials in single crystal ZrN, whereas at high temperatures Xe may diffuse in ZrN assisted by vacancies.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation (NA-20); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1372349
• Journal Information: Computational Materials Science, Journal Name: Computational Materials Science Vol. 133; ISSN 0927-0256
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
First-principles
Fission gas incorporation and migration
Zirconium nitride