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Photoreduction of Pu(V,VI) by TiO2

Anna Yu. Romanchuk, Stepan N. Kalmykov, Alexander V. Egorov, Yan V. Zubavichus, Andrei A. Shiryaev, Eugene A. Smirnov and Alexey V. Garshev
From the journal Radiochimica Acta

Abstract

In this study, the effect of light on the kinetics and speciation of plutonium at its interaction with particles of TiO2 under different light conditions is shown for the first time. It was found that sorption was followed by reduction of the plutonium to Pu(IV). In this, the reduction reaction and sorption in conditions of the presence of light proceed significantly more rapidly due to the photocatalytic activity of titanium dioxide, providing a source of electrons for the reaction. Spectral methods (XAFS and TEM) showed that plutonium forms nanoclusters with the structure of PuO2, which decorate the surface of the solid phase.

Funding source: Russian Science Foundation

Award Identifier / Grant number: 14-13-01279

Funding statement: This work was supported by the Russian Science Foundation (project 14-13-01279). We also acknowledge the “Nanochemistry and nanomaterials” user facility of the Department of Chemistry of MSU for providing the HRTEM measurements.

Acknowledgments

This work was supported by the Russian Science Foundation (project 14-13-01279). We also acknowledge the “Nanochemistry and nanomaterials” user facility of the Department of Chemistry of MSU for providing the HRTEM measurements.

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Supplemental Material:

The online version of this article (DOI: 10.1515/ract-2015-2494) offers supplementary material, available to authorized users.

Received: 2015-8-2
Accepted: 2016-6-25
Published Online: 2016-8-25
Published in Print: 2016-12-1

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