Infrared Spectra of Uranium Oxides Measured by ATR-FTIR

Abstract

The infrared spectra of uranium oxides (UO x) of various O/U ratios (x ¼ 2{2:667 in UO x) were measured by using ATR-FTIR in order to investigate the applicability of ATR technology to the characterization of uranium oxides or nuclear fuel. The samples of uranium oxides (UO x) were prepared by heating UO 2 powder in air atmosphere followed by weighing to determine the gains by oxygen. X-ray diffraction (XRD) patterns for the same samples of infrared spectra were measured to get information on their phases on uranium oxides (UO x) with increasing x. The measured characteristic bands from UO x samples could be assigned well by referring to the spectra reported in the literature and comparing with the diffraction patterns measured. The relationship between absorbance and O/U ratio (x) was determined. We discussed about using it for the O/U ratio estimation of uranium oxides of unknown composition. It was confirmed that ATR technology for infrared spectroscopy can be useful for the studies of radioactive materials that are difficult to handle using conventional methods.

Room temperature synthesis of UO2+x nanocrystals and thin films via hydrolysis of uranium(iv) complexes

“…In addition, there is a broad, ill-defined shoulder at ca. 750 cm −1 in UO 2 -1, which has been shown to appear in samples of hyperstoichiometric UO 2+x , 42 signifying a higher oxide content.…”

“…S7 †). 41,42 Based upon the lack of additional features in the IR spectra, we tentatively assign these bands to the presence of residual organic material. In addition, there is a broad, ill-defined shoulder at ca.…”

“…UO 2 possesses one broad absorption band in the IR region at 445 cm −1 but is otherwise featureless unless higher oxides are present. [39][40][41][42] As compared to the FT-IR (KBr pellet) of commercially purchased UO 2 , the spectra of UO 2 -1 and UO 2 -2 exhibit a few additional absorption bands, with a prominent peak in both at 906 cm −1 and a peak at 1550 cm −1 in UO 2 -1, absorptions that cannot be attributed to hyperstoichiometric UO 2+x (Fig. S7 †).…”

Application of Visible/Near-Infrared Reflectance Spectroscopy to Uranium Ore Concentrates for Nuclear Forensic Analysis and Attribution

“…Infrared spectroscopy of UOC materials to characterize the different classes of UOC materials has been reported by several different groups. 13–20 Eidson investigated synthesized mixtures of ADU and U 3 O 8 by transmission infrared (IR) spectroscopy with the goal to determine speciation in urine samples. 13 Kim et al used attenuated total reflectance (ATR) IR spectroscopy of uranium oxides to determine the oxygen-to-uranium (O/U) ratio, which was varied by heating in air.…”

“…X-ray diffraction was used to determine the ratios, and primary IR bands at 638 and 715 cm −1 were monitored. 14 Allen and Holmes used a transmission IR (cesium iodide [CsI] or potassium bromide [KBr]) press to study binary uranium oxides of UO 2 , uranium(IV, V) oxide (U 4 O 9 ), triuranium heptaoxide (U 3 O 7 ), and UO 3 in different crystal phases. 15 Reaction mechanisms to produce ammonium uranates (AUs) were studied with diffuse reflectance IR spectroscopy by Lin et al, while Rofail investigated ammonium uranyl carbonates (AUCs) by IR spectroscopy and provided band assignments for vibrational modes of ammonia (NH 3 ), carbonate (CO 3 ), and U species.…”