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DFT + U Study of the Adsorption and Dissociation of Water on Clean, Defective, and Oxygen-Covered U(3)Si(2){001}, {110}, and {111} Surfaces
[Image: see text] The interfacial interaction of U(3)Si(2) with water leads to corrosion of nuclear fuels, which affects various processes in the nuclear fuel cycle. However, the mechanism and molecular-level insights into the early oxidation process of U(3)Si(2) surfaces in the presence of water an...
Autores principales: | , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Chemical
Society
2019
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7011762/ https://www.ncbi.nlm.nih.gov/pubmed/32064013 http://dx.doi.org/10.1021/acs.jpcc.9b03076 |
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author | Jossou, Ericmoore Malakkal, Linu Dzade, Nelson Y. Claisse, Antoine Szpunar, Barbara Szpunar, Jerzy |
author_facet | Jossou, Ericmoore Malakkal, Linu Dzade, Nelson Y. Claisse, Antoine Szpunar, Barbara Szpunar, Jerzy |
author_sort | Jossou, Ericmoore |
collection | PubMed |
description | [Image: see text] The interfacial interaction of U(3)Si(2) with water leads to corrosion of nuclear fuels, which affects various processes in the nuclear fuel cycle. However, the mechanism and molecular-level insights into the early oxidation process of U(3)Si(2) surfaces in the presence of water and oxygen are not fully understood. In this work, we present Hubbard-corrected density functional theory (DFT + U) calculations of the adsorption behavior of water on the low Miller indices of the pristine and defective surfaces as well as water dissociation and accompanied H(2) formation mechanisms. The adsorption strength decreases in the order U(3)Si(2){001} > U(3)Si(2){110} > U(3)Si(2){111} for both molecular and dissociative H(2)O adsorption. Consistent with the superior reactivity, dissociative water adsorption is most stable. We also explored the adsorption of H(2)O on the oxygen-covered U(3)Si(2) surface and showed that the preadsorbed oxygen could activate the OH bond and speed up the dissociation of H(2)O. Generally, we found that during adsorption on the oxygen-covered, defective surface, multiple water molecules are thermodynamically more stable on the surface than the water monomer on the pristine surface. Mixed molecular and dissociative water adsorption modes are also noted to be stable on the {111} surface, whereas fully dissociative water adsorption is most stable on the {110} and {001} surfaces. |
format | Online Article Text |
id | pubmed-7011762 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | American Chemical
Society |
record_format | MEDLINE/PubMed |
spelling | pubmed-70117622020-02-12 DFT + U Study of the Adsorption and Dissociation of Water on Clean, Defective, and Oxygen-Covered U(3)Si(2){001}, {110}, and {111} Surfaces Jossou, Ericmoore Malakkal, Linu Dzade, Nelson Y. Claisse, Antoine Szpunar, Barbara Szpunar, Jerzy J Phys Chem C Nanomater Interfaces [Image: see text] The interfacial interaction of U(3)Si(2) with water leads to corrosion of nuclear fuels, which affects various processes in the nuclear fuel cycle. However, the mechanism and molecular-level insights into the early oxidation process of U(3)Si(2) surfaces in the presence of water and oxygen are not fully understood. In this work, we present Hubbard-corrected density functional theory (DFT + U) calculations of the adsorption behavior of water on the low Miller indices of the pristine and defective surfaces as well as water dissociation and accompanied H(2) formation mechanisms. The adsorption strength decreases in the order U(3)Si(2){001} > U(3)Si(2){110} > U(3)Si(2){111} for both molecular and dissociative H(2)O adsorption. Consistent with the superior reactivity, dissociative water adsorption is most stable. We also explored the adsorption of H(2)O on the oxygen-covered U(3)Si(2) surface and showed that the preadsorbed oxygen could activate the OH bond and speed up the dissociation of H(2)O. Generally, we found that during adsorption on the oxygen-covered, defective surface, multiple water molecules are thermodynamically more stable on the surface than the water monomer on the pristine surface. Mixed molecular and dissociative water adsorption modes are also noted to be stable on the {111} surface, whereas fully dissociative water adsorption is most stable on the {110} and {001} surfaces. American Chemical Society 2019-07-11 2019-08-15 /pmc/articles/PMC7011762/ /pubmed/32064013 http://dx.doi.org/10.1021/acs.jpcc.9b03076 Text en Copyright © 2019 American Chemical Society This is an open access article published under a Creative Commons Attribution (CC-BY) License (http://pubs.acs.org/page/policy/authorchoice_ccby_termsofuse.html) , which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited. |
spellingShingle | Jossou, Ericmoore Malakkal, Linu Dzade, Nelson Y. Claisse, Antoine Szpunar, Barbara Szpunar, Jerzy DFT + U Study of the Adsorption and Dissociation of Water on Clean, Defective, and Oxygen-Covered U(3)Si(2){001}, {110}, and {111} Surfaces |
title | DFT + U Study of the Adsorption and
Dissociation of Water on Clean, Defective, and Oxygen-Covered U(3)Si(2){001}, {110}, and {111} Surfaces |
title_full | DFT + U Study of the Adsorption and
Dissociation of Water on Clean, Defective, and Oxygen-Covered U(3)Si(2){001}, {110}, and {111} Surfaces |
title_fullStr | DFT + U Study of the Adsorption and
Dissociation of Water on Clean, Defective, and Oxygen-Covered U(3)Si(2){001}, {110}, and {111} Surfaces |
title_full_unstemmed | DFT + U Study of the Adsorption and
Dissociation of Water on Clean, Defective, and Oxygen-Covered U(3)Si(2){001}, {110}, and {111} Surfaces |
title_short | DFT + U Study of the Adsorption and
Dissociation of Water on Clean, Defective, and Oxygen-Covered U(3)Si(2){001}, {110}, and {111} Surfaces |
title_sort | dft + u study of the adsorption and
dissociation of water on clean, defective, and oxygen-covered u(3)si(2){001}, {110}, and {111} surfaces |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7011762/ https://www.ncbi.nlm.nih.gov/pubmed/32064013 http://dx.doi.org/10.1021/acs.jpcc.9b03076 |
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