TY - JOUR
T1 - Molecular dynamics simulation of reduced CeO2
AU - Cui, Zhiwei
AU - Sun, Yi
AU - Qu, Jianmin
N1 - Publisher Copyright:
© 2012 Elsevier B.V. All rights reserved.
PY - 2012/10/15
Y1 - 2012/10/15
N2 - In this paper, the mechanical properties and oxygen self-diffusion in partially reduced CeO2 have been investigated by using molecular dynamics simulations at various levels of non-stoichiometry and temperatures. Under a reducing environment, pure ceria experiences significant chemical volumetric expansion, which is described by coefficient of compositional expansion (CCE). It is found that CCE is about 0.084 and varies within 2% over the whole range of temperature. Meanwhile, elastic stiffness tensor of the non-stoichiometric structures remains cubic. The Young's modulus decreases with increasing vacancy concentration, while the variation of the Poisson's ratio is found to be negligible. The oxygen diffusivity is computed by mean square displacements which increase initially but descend with increasing non-stoichiometry. In addition, the oxygen migration energy is extrapolated to be 0.4 eV which is consistent with reported experiment data.
AB - In this paper, the mechanical properties and oxygen self-diffusion in partially reduced CeO2 have been investigated by using molecular dynamics simulations at various levels of non-stoichiometry and temperatures. Under a reducing environment, pure ceria experiences significant chemical volumetric expansion, which is described by coefficient of compositional expansion (CCE). It is found that CCE is about 0.084 and varies within 2% over the whole range of temperature. Meanwhile, elastic stiffness tensor of the non-stoichiometric structures remains cubic. The Young's modulus decreases with increasing vacancy concentration, while the variation of the Poisson's ratio is found to be negligible. The oxygen diffusivity is computed by mean square displacements which increase initially but descend with increasing non-stoichiometry. In addition, the oxygen migration energy is extrapolated to be 0.4 eV which is consistent with reported experiment data.
KW - Ceria
KW - Coefficient of compositional expansion
KW - Diffusivity
KW - Elastic constants
KW - Molecular dynamics simulation
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U2 - 10.1016/j.ssi.2012.08.001
DO - 10.1016/j.ssi.2012.08.001
M3 - Article
AN - SCOPUS:84865823318
SN - 0167-2738
VL - 226
SP - 24
EP - 29
JO - Solid State Ionics
JF - Solid State Ionics
ER -