Structural stability of REE-PO₄ (REE = Sm,Tb) under swift heavy ion irradiation

Journal Article · Sat Aug 06 00:00:00 EDT 2022 · Nuclear Instruments and Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms

DOI:https://doi.org/10.1016/j.nimb.2022.07.014· OSTI ID:1883846

Overstreet, Cale ^[1]; Cooper, Jacob ^[1]; O'Quinn, Eric ^[1]; Cureton, William ^[2]; Palomares, Raul ^[1]; Leys, Julia ^[3]; Deissmann, Guido ^[4]; Neumeier, Stefan ^[4]; Chen, Chien-Hung ^[5]; Lang, Maik ^[1]

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1. University of Tennessee, Knoxville, TN (United States)
2. University of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
3. Forschungszentrum Jülich GmbH, Julich (Germany); Karlsruhe Institute of Technology (KIT) (Germany)
4. Forschungszentrum Jülich GmbH, Julich (Germany)
5. Stanford University, CA (United States)

We report rare earth element (REE) phosphates are an attractive host matrix for long-lived radionuclides from nuclear waste because of the radiation tolerance exhibited by naturally occurring REE phosphate specimens. Here we show that SmPO₄ (monazite structure) and TbPO₄ (xenotime structure) exhibit a similar amorphization response to swift heavy ion irradiation despite different starting structures. SmPO₄ and TbPO₄ were irradiated with 1.1 GeV Au ions and analyzed using synchrotron-based X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM). The radiation response of the phosphates was evaluated by extracting the amorphous fraction at each irradiation fluence, and a single-impact model was used to determine the amorphous cross section and track diameter. Amorphization within individual ion tracks was confirmed using head-on TEM imaging, and the amorphous track size agreed with the value deduced by XRD analysis. Raman measurements were performed to qualitatively confirm the ion-induced crystalline-to-amorphous transformation which proceeds similarly for both phosphates.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Univ. of Illinois, Chicago, IL (United States); Univ. of Tennessee, Knoxville, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES); University of Tennessee; USDOE National Nuclear Security Administration (NNSA), Office of Defense Programs (DP); USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division (MSE)
• Grant/Contract Number: AC05-00OR22725; SC0020321; AC02-06CH11357; NA0003975
• OSTI ID: 1883846
• Alternate ID(s): OSTI ID: 1901277; OSTI ID: 2328613
• Journal Information: Nuclear Instruments and Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms, Vol. 527, Issue 15; ISSN 0168-583X
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
REE-phosphates
monazite
xenotime
nuclear waste form
ion irradiation
x-ray diffraction
Raman spectroscopy
crystalline-to-amorphous transformation
REE-phosphates
monazite
xenotime
nuclear waste form
ion irradiation
X-ray diffraction
Raman spectroscopy
crystalline-to-amorphous transformation