Dependence of UO<sub>2</sub> surface morphology on processing history within a single synthetic route

Abbott, Erik C.; Brenkmann, Alexandria; Galbraith, Craig S.; Ong, Joshua; Schwerdt, Ian J.; Albrecht, Brent D.; Taşdizen, Tolga; McDonald, Luther W.

doi:10.1515/ract-2018-3065

Cited by 16 publications

(19 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The graphene purity was > 95% (impurities: free carbon: ~4.7%, Fe: ~0.3%) [11]. The purity of the UO 2 powder was > 99.5%, with a median particle size of ~30 µm [12]. Concentrated sulfuric acid (18.4 mol/L), concentrated nitric acid (15.2 mol/L), ammonia (13.33 mol/L), anhydrous ethanol (98%, mass fraction), and Ar-5% H 2 mixed gas were used.…”

Section: Methodsmentioning

confidence: 99%

Mechanism and Properties of UO2–Graphene Composite Fuel Prepared by In Situ Synthesis

Yin

2022

Crystals

View full text Add to dashboard Cite

A nucleation method based on a composite of uranium dioxide (UO2) and graphene is presented by in situ synthesis, and the relevant mechanism and fuel properties are investigated. UO2–graphene composite fuel powders containing graphene volume (2%, 4%, 6%, and 8%) were prepared using a nucleation method through the reactive deposition of uranyl nitrate and aqueous ammonia on graphene by controlling the reaction parameters. The composite fuel pellets were prepared using spark plasma sintering (SPS). The results showed that the uniformity of UO2–graphene powder prepared by in situ synthesis reached up to 96.39%. An analysis on the relevant phase structure showed that only UO2 and graphene existed in the sintered pellets at 1723 K, graphene and UO2 were not destroyed during the reaction, and the pellet densities for the in-situ synthesis were 95.56%TD, 95.32%TD, 95.08%TD, and 94.76%TD for graphene contents of 2%, 4%, 6%, and 8%, respectively. The thermal conductivities of pellets at 293 K increased by 12.27%, 20.13%, 27.47%, and 34.13%, and by 18.36%, 35.00%, 47.07%, and 58.93% at 1273 K for 2%, 4%, 6%, and 8% graphene contents, respectively. The performance of graphene in the fuel was superior at high temperatures, which overcame shortcomings due to the low thermal conductivity of UO2 at high temperatures. SEM results showed that the grain sizes of the pellets prepared by synthesis in situ were 10–30 μm, and there was no obvious pore at the grain boundary because the grains were closely bound. The graphene was uniformly coated by UO2, and the thermal conductivity of the pellets improved upon the formation of a bridging heat conduction network.

show abstract

Section: Methodsmentioning

confidence: 99%

Mechanism and Properties of UO2–Graphene Composite Fuel Prepared by In Situ Synthesis

Yin

2022

Crystals

View full text Add to dashboard Cite

show abstract

“…Abbott et al studied UO 2 prepared by H 2 reduction of three different uranium oxide precursors, am-UO 3 , α-UO 3 , and α-U 3 O 8 . 20 They observed that the morphology for each UO 2 material was qualitatively distinct from one another and the morphology of each UO 2 material was qualitatively similar to that of the uranium oxide from which it was prepared. The UO 2 prepared from α-UO 3 was significantly distinct from the other UO 2 samples, and thus additional analysis was not performed.…”

Section: ■ Uocsmentioning

confidence: 97%

“…In particular, recent research has examined the morphology of various uranium oxides, with a focus on discerning process history or process conditions for a particular sample of material. [20][21][22][23][24][25][26][27][28][29][30][31][32]46 One outcome of these efforts was a lexicon to standardize descriptions of material images for nuclear forensics, indicating a likely increasing role for morphology within nuclear forensics. 33 Recent research has also investigated elemental and chemical impurities present in process samples of uranium compounds, also with a focus of discerning process history as well as the origin of the uranium.…”

Section: ■ Introductionmentioning

confidence: 99%

“…Over the past decade, a significant research effort has focused on several of these key uranium compounds with the aim of advancing the science of these compounds and the field of nuclear forensics. In particular, recent research has examined the morphology of various uranium oxides, with a focus on discerning process history or process conditions for a particular sample of material. − , One outcome of these efforts was a lexicon to standardize descriptions of material images for nuclear forensics, indicating a likely increasing role for morphology within nuclear forensics . Recent research has also investigated elemental and chemical impurities present in process samples of uranium compounds, also with a focus of discerning process history as well as the origin of the uranium. − ,,,− For example, the concentrations of rare-earth elements (REEs) have been found to be potentially useful for identifying the origin of UOCs .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Progress in Uranium Chemistry: Driving Advances in Front-End Nuclear Fuel Cycle Forensics

et al. 2021

View full text Add to dashboard Cite

The front-end of the nuclear fuel cycle encompasses several chemical and physical processes used to acquire and prepare uranium for use in a nuclear reactor. These same processes can also be used for weapons or nefarious purposes, necessitating the need for technical means to help detect, investigate, and prevent the nefarious use of nuclear material and nuclear fuel cycle technology. Over the past decade, a significant research effort has investigated uranium compounds associated with the front-end of the nuclear fuel cycle, including uranium ore concentrates (UOCs), UF 4 , UF 6 , and UO 2 F 2 . These efforts have furthered uranium chemistry with an aim to expand and improve the field of nuclear forensics. Focus has been given to the morphology of various uranium compounds, trace elemental and chemical impurities in process samples of uranium compounds, the degradation of uranium compounds, particularly under environmental conditions, and the development of improved or new techniques for analysis of uranium compounds. Overall, this research effort has identified relevant chemical and physical characteristics of uranium compounds that can be used to help discern the origin, process history, and postproduction history for a sample of uranium material. This effort has also identified analytical techniques that could be brought to bear for nuclear forensics purposes. Continued research into these uranium compounds should yield additional relevant chemical and physical characteristics and analytical approaches to further advance front-end nuclear fuel cycle forensics capabilities.

show abstract

“…shown to be a result of processing parameters including dependence on the starting material, 1 intermediate material, 2 oxidation rates, 3 precipitation conditions, 4 and thermal history. 5 These were the first studies to successfully quantify morphological analysis of nuclear material and were essential to advancements in nuclear forensics and the nuclear fuels community.…”

mentioning

confidence: 99%

Quantifying Impurity Effects on the Surface Morphology of α-U₃O₈

Hanson

Lee

Vachet³

et al. 2019

Anal. Chem.

Self Cite

View full text Add to dashboard Cite

The morphological effect of impurities on α-U3O8 has been investigated. This study provides the first evidence that the presence of impurities can alter nuclear material morphology, and these changes can be quantified to aid in revealing processing history. Four elements: Ca, Mg, V, and Zr were implemented in the uranyl peroxide synthesis route and studied individually within the α-U3O8. Six total replicates were synthesized, and replicates 1–3 were filtered and washed with Millipore water (18.2 MΩ) to remove any residual nitrates. Replicates 4–6 were filtered but not washed to determine the amount of impurities removed during washing. Inductively coupled plasma mass spectrometry (ICP-MS) was employed at key points during the synthesis to quantify incorporation of the impurity. Each sample was characterized using powder X-ray diffraction (p-XRD), high-resolution scanning electron microscopy (HRSEM), and SEM with energy dispersive X-ray spectroscopy (SEM-EDS). p-XRD was utilized to evaluate any crystallographic changes due to the impurities; HRSEM imagery was analyzed with Morphological Analysis for MAterials (MAMA) software and machine learning classification for quantification of the morphology; and SEM-EDS was utilized to locate the impurity within the α-U3O8. All samples were found to be quantifiably distinguishable, further demonstrating the utility of quantitative morphology as a signature for the processing history of nuclear material.

show abstract

Dependence of UO₂ surface morphology on processing history within a single synthetic route

Cited by 16 publications

References 27 publications

Mechanism and Properties of UO2–Graphene Composite Fuel Prepared by In Situ Synthesis

Mechanism and Properties of UO2–Graphene Composite Fuel Prepared by In Situ Synthesis

Progress in Uranium Chemistry: Driving Advances in Front-End Nuclear Fuel Cycle Forensics

Quantifying Impurity Effects on the Surface Morphology of α-U₃O₈

Contact Info

Product

Resources

About

Dependence of UO2 surface morphology on processing history within a single synthetic route

Cited by 16 publications

References 27 publications

Mechanism and Properties of UO2–Graphene Composite Fuel Prepared by In Situ Synthesis

Mechanism and Properties of UO2–Graphene Composite Fuel Prepared by In Situ Synthesis

Progress in Uranium Chemistry: Driving Advances in Front-End Nuclear Fuel Cycle Forensics

Quantifying Impurity Effects on the Surface Morphology of α-U3O8

Contact Info

Product

Resources

About

Dependence of UO₂ surface morphology on processing history within a single synthetic route

Quantifying Impurity Effects on the Surface Morphology of α-U₃O₈