Mechanisms of the defect formation and diffusion of cations on the surface of uranium dioxide nanocrystals: Molecular dynamics study / Kovalenko M. A.,Kupryazhkin A. Ya // JOURNAL OF NUCLEAR MATERIALS. - 2015. - V. 459, l. . - P. 20-29.

ISSN/EISSN:

0022-3115 / 1873-4820

Type:

Article

Abstract:

Mass transfer and cation diffusion mechanisms on the surface of UO2 nanocrystal were investigated by the high-speed MD method using GPU. Stoichiometric uranium dioxide nanocrystals of 12,000 ions were simulated with two interaction potentials sets. Three regions on the nanocrystal surface with significantly different activation energies were separated. It is shown that the overall mass transfer on the surface is limited by the diffusion of cations on edges connecting (1 0 0) facets. The calculated diffusion activation energy of 5.2 eV is close to the experimental one of 4.7 eV. Estimations of the thickness of the diffusion surface layer were carried out. It is shown that the diffusion of cations in the bulk is fully associated with the migration of Schottky cation vacancies, which are formed on (1 0 0) surfaces. The calculated formation energy of a Schottky trio of 6.6 eV is close to the experimental estimation of 6.5 eV, but significantly differs from the value of 9.8 eV, derived by the standard lattice statics method. (C) 2015 Elsevier B.V. All rights reserved.

Author keywords:

MASS-TRANSPORT; UO2; POTENTIALS; SIMULATION

DOI:

10.1016/j.jnucmat.2015.01.003

Web of Science ID:

ISI:000350710700004

Соавторы в МНС:

Другие поля

Поле	Значение
Month	APR
Publisher	ELSEVIER SCIENCE BV
Address	PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
Language	English
EISSN	1873-4820
Keywords-Plus	MASS-TRANSPORT; UO2; POTENTIALS; SIMULATION
Research-Areas	Materials Science; Nuclear Science \& Technology
Web-of-Science-Categories	Materials Science, Multidisciplinary; Nuclear Science \& Technology
Author-Email	akm\_max@mail.ru kupr@dpt.ustu.ru
Funding-Acknowledgement	UrFU
Funding-Text	This research project has been supported by UrFU under the Framework Programme of development of UrFU through the Young scientists UrFU competition.
Number-of-Cited-References	14
Usage-Count-Last-180-days	3
Usage-Count-Since-2013	22
Journal-ISO	J. Nucl. Mater.
Doc-Delivery-Number	CC9SE