Raman spectroscopic study of the structural change of uranium–thorium-mixed oxides before and after oxidation

• Published in: Journal of radioanalytical and nuclear chemistry Vol. 316; no. 3; pp. 1295 - 1300
• Main Authors: Lee, Jeongmook, Kim, Jandee, Youn, Young-Sang, Kim, Jong-Yun, Lim, Sang Ho
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.06.2018; Springer; Springer Nature B.V
• Subjects: Carbon dioxide; Chemistry; Chemistry and Materials Science; Diagnostic Radiology; Doping; Fluorite; Hadrons; Heavy Ions; Inorganic Chemistry; Mixed oxides; Nuclear Chemistry; Nuclear energy; Nuclear Physics; Oxidation; Oxidation-reduction reactions; Oxides; Pellets; Physical Chemistry; Raman spectra; Raman spectroscopy; Spectrum analysis; Thorium; Uranium; Uranium dioxide; Oxidation; Defect structure; Uranium oxide; Raman spectroscopy; Actinide oxide; Mixed oxide
• ISSN: 0236-5731; 1588-2780
• DOI: 10.1007/s10967-018-5829-x

UO 2 pellets doped with 1, 5 and 10 mol% Th before and after oxidation were analyzed by using Raman spectroscopy to investigate the Th doping effect on the structural changes during oxidation of UO 2 . While the Raman spectra of all sample pellets showed a close-to-perfect fluorite structure before oxidation, those of oxidized (U 1− y Th y )O 2+ x (0.03 ≤  x  ≤ 0.06) pellets showed distinct defect structures after oxidation at 1150 °C with CO/CO 2  = 0.001. The increasing relative ratio of first-order longitudinal optical modes of (U 1− y Th y )O 2+ x with increasing doping levels should represent the defect structure due to the Th doping effect.