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A Novel Metastable Pentavalent Plutonium Solid Phase on the Pathway from Aqueous Plutonium(VI) to PuO₂ Nanoparticles.

ABSTRACT: Here we provide evidence that the formation of PuO₂ nanoparticles from oxidized Pu^VI under alkaline conditions proceeds through the formation of an intermediate Pu^V solid phase, similar to NH₄ PuO₂ CO₃ , which is stable over a period of several months. For the first time, state-of-the-art experiments at Pu M₄ and at L₃ absorption edges combined with theoretical calculations unambiguously allow to determine the oxidation state and the local structure of this intermediate phase.

SUBMITTER: Kvashnina KO

PROVIDER: S-EPMC6900038 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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A Novel Metastable Pentavalent Plutonium Solid Phase on the Pathway from Aqueous Plutonium(VI) to PuO2 Nanoparticles.

Kvashnina Kristina O KO Romanchuk Anna Yu AY Pidchenko Ivan I Amidani Lucia L Gerber Evgeny E Trigub Alexander A Rossberg Andre A Weiss Stephan S Popa Karin K Walter Olaf O Caciuffo Roberto R Scheinost Andreas C AC Butorin Sergei M SM Kalmykov Stepan N SN

Angewandte Chemie (International ed. in English) 20191106 49

Here we provide evidence that the formation of PuO2 nanoparticles from oxidized PuVI under alkaline conditions proceeds through the formation of an intermediate PuV solid phase, similar to NH4 PuO2 CO3 , which is stable over a period of several months. For the first time, state-of-the-art experiments at Pu M4 and at L3 absorption edges combined with theoretical calculations unambiguously allow to determine th ...[more]

PMID: 31621992

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