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Defect-induced phonon-resonant scattering and its influence on thermal transport of irradiated thorium-dioxide

Adnan, Saqeeb [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0000000302465947)·Khanolkar, Amey Rajendra [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000308165507)·Hua, Zilong [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000229423344)·Minaruzzaman, Md [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0009000316951505)·Alshannaq, Mutaz [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0009000362663598)·Ferrigno, Joshua [The Ohio State Univ., Columbus, OH (United States)]·Prusnick, Timothy A. [KBR, Dayton, OH (United States)] (ORCID:0009000209659533)·Jin, Miaomiao [Pennsylvania State Univ., University Park, PA (United States)] (ORCID:0000000235434082)·Mann, J. Matthew [Air Force Research Lab. (AFRL), Wright-Patterson AFB, OH (United States)] (ORCID:0000000289124346)·Hurley, David H. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000218451518)·Khafizov, Marat [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0000000181713528)
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Abstract

Thermal transport in proton irradiated thorium-dioxide (ThO 2 ) is investigated. Using a combination of experiments and first-principles computational framework, the role of lattice defects on thermal conductivity is analyzed. A resonant-phonon scattering mechanism beyond the traditionally considered Rayleigh scattering is found to significantly influence low-temperature thermal transport in the presence of irradiation-induced point defects. The existence of localized phonon modes associated with irradiation-induced defects is suggested by the inability of the first-principles based thermal conductivity model—which considers only three-phonon interactions and phonon-defects scattering using the Tamura formalism—to predict the experimental results, unless a resonant scattering mechanism is included. The emergence of additional peaks in the Raman spectra in the proximity of phonon-resonant frequency provides further evidence for the existence of localized modes. Coupled with a microstructure evolution model, this analysis enables more accurate analysis for contrasting the contributions of different phonon scattering mechanisms across all irradiation doses and temperatures.

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11 - NUCLEAR FUEL CYCLE AND FUEL MATERIALS11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS36 - MATERIALS SCIENCE36 MATERIALS SCIENCE75 - CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYActinidesBoltzmann transport equationsCrystallographic defectsDensity functional theoryIon radiation effectsLocal vibrational mode spectroscopyPhonon scatteringRaman spectroscopyThermal transportTransmission electron microscopyion irradiationlattice defectsnuclear fuelthorium dioxide

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Adnan, Saqeeb [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0000000302465947), Khanolkar, Amey Rajendra [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000308165507), Hua, Zilong [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000229423344), Minaruzzaman, Md [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0009000316951505), Alshannaq, Mutaz [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0009000362663598), Ferrigno, Joshua [The Ohio State Univ., Columbus, OH (United States)], Prusnick, Timothy A. [KBR, Dayton, OH (United States)] (ORCID:0009000209659533), Jin, Miaomiao [Pennsylvania State Univ., University Park, PA (United States)] (ORCID:0000000235434082), Mann, J. Matthew [Air Force Research Lab. (AFRL), Wright-Patterson AFB, OH (United States)] (ORCID:0000000289124346), Hurley, David H. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000218451518), Khafizov, Marat [The Ohio State Univ., Columbus, OH (United States)] (ORCID:0000000181713528). 2025-10-03. Defect-induced phonon-resonant scattering and its influence on thermal transport of irradiated thorium-dioxide. https://doi.org/10.1063/5.0290898

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