TY - JOUR
T1 - Measurement of radiation-enhanced diffusion of la in single crystal thin film CeO2
AU - Pappas, Harrison K.
AU - Heuser, Brent J.
AU - Strehle, Melissa M.
N1 - Funding Information:
This work was performed with support from the US Department of Energy Nuclear Energy Research Initiative under Grant No. DEFG-07-14891 . In addition, this work was carried out in part in the Frederick Seitz Materials Research Laboratory Central Facilities, University of Illinois, which are partially supported by the US Department of Energy under Grants DE-FG02-07ER46453 and DE-FG02-07ER46471 . The film used in this study was grown by M. Zhang, a member of J. Eckstein’s research group at the Univ. of Illinois, and this is gratefully acknowledged. The assistance of T. Spila (SIMS), D. Jeffers (ion accelerator), S. Burdin (profilometry), H. Ju (XRD), M. El-Bakhshwan (ion bombardment), X. Han (ion bombardment), and D. Heuser (data fitting) are all gratefully acknowledged. Finally, the authors are grateful to R. Averback for the use of the heated irradiation sample stage, for useful discussions regarding radiation-enhanced diffusivity, and for general interest in the work.
PY - 2010/10/15
Y1 - 2010/10/15
N2 - The diffusion of La, a trivalent cation dopant, actinide surrogate, and high-yield fission product, in CeO2, a UO2 nuclear fuel surrogate, during 1.8 MeV Kr+ ion bombardment over a temperature range from 673 K to 1206 K has been measured with secondary ion mass spectroscopy. The diffusivity under these irradiation conditions has been analyzed with a model based on a combination of sink-limited and recombination-limited kinetics. This analysis yielded a cation vacancy migration energy of Emv ∼ 0.4 eV below ∼800 K, were recombination-limited kinetics dominated the behavior. The thermal diffusivity of La in the same system was measured over a range of 873-1073 K and was characterized by an activation enthalpy of Ea=Efv+Emv∼1.4eV. The measurement of both the migration enthalpy and total activation enthalpy separately allows the vacancy formation enthalpy on the cation sublattice to be determined; Efv ∼ 1 eV. The mixing parameter under energetic heavy-ion bombardment at room temperature was measured as well and found to be ∼4 × 10-5 nm 5/eV.
AB - The diffusion of La, a trivalent cation dopant, actinide surrogate, and high-yield fission product, in CeO2, a UO2 nuclear fuel surrogate, during 1.8 MeV Kr+ ion bombardment over a temperature range from 673 K to 1206 K has been measured with secondary ion mass spectroscopy. The diffusivity under these irradiation conditions has been analyzed with a model based on a combination of sink-limited and recombination-limited kinetics. This analysis yielded a cation vacancy migration energy of Emv ∼ 0.4 eV below ∼800 K, were recombination-limited kinetics dominated the behavior. The thermal diffusivity of La in the same system was measured over a range of 873-1073 K and was characterized by an activation enthalpy of Ea=Efv+Emv∼1.4eV. The measurement of both the migration enthalpy and total activation enthalpy separately allows the vacancy formation enthalpy on the cation sublattice to be determined; Efv ∼ 1 eV. The mixing parameter under energetic heavy-ion bombardment at room temperature was measured as well and found to be ∼4 × 10-5 nm 5/eV.
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U2 - 10.1016/j.jnucmat.2010.07.042
DO - 10.1016/j.jnucmat.2010.07.042
M3 - Article
AN - SCOPUS:77956613659
VL - 405
SP - 118
EP - 125
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
SN - 0022-3115
IS - 2
ER -