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

Abstract

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.

Authors:
 [1];  [1];  [1]
  1. Argonne National Lab. (ANL), Argonne, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation (NA-20); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1372349
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Computational Materials Science
Additional Journal Information:
Journal Volume: 133; Journal ID: ISSN 0927-0256
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Zirconium nitride; Fission gas incorporation and migration; First-principles

Citation Formats

Mei, Zhi-Gang, Liang, Linyun, and Yacout, Abdellatif M. First-principles study of fission gas incorporation and migration in zirconium nitride. United States: N. p., 2017. Web. doi:10.1016/j.commatsci.2017.03.019.
Mei, Zhi-Gang, Liang, Linyun, & Yacout, Abdellatif M. First-principles study of fission gas incorporation and migration in zirconium nitride. United States. doi:10.1016/j.commatsci.2017.03.019.
Mei, Zhi-Gang, Liang, Linyun, and Yacout, Abdellatif M. Fri . "First-principles study of fission gas incorporation and migration in zirconium nitride". United States. doi:10.1016/j.commatsci.2017.03.019. https://www.osti.gov/servlets/purl/1372349.
@article{osti_1372349,
title = {First-principles study of fission gas incorporation and migration in zirconium nitride},
author = {Mei, Zhi-Gang and Liang, Linyun and Yacout, Abdellatif M.},
abstractNote = {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.},
doi = {10.1016/j.commatsci.2017.03.019},
journal = {Computational Materials Science},
number = ,
volume = 133,
place = {United States},
year = {Fri Mar 24 00:00:00 EDT 2017},
month = {Fri Mar 24 00:00:00 EDT 2017}
}

Journal Article:
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