The environmental dependence of redox energetics of PuO2 and α-Pu2O3: A quantitative solution from

2012/08/01 by Bo Sun, Haifeng Liu, Haifeng Song +5
Chemistry · Materials Science · Physics and Astronomy · #Chemistry #Energetics #Inorganic chemistry #Nuclear Materials and Properties #Nuclear materials and radiation effects #Physics #Radioactive element chemistry and processing #Redox #Thermodynamics #cond-mat.mtrl-sci

paper · pdf · doi:10.1016/j.physleta.2012.07.030

published as Physics Letters A 376 (2012) 2672-2676 · 5 PLA pages, 4 figures

openalex publication_date 2012/08/01 · arxiv created 2012/08/18 · arxiv updated 2012/08/21 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We report a comprehensive density functional theory (DFT) + U study of the energetics of charged and neutral oxygen defects in both PuO₂ and α-Pu₂O₃, and present a quantitative determination of the equilibrium compositions of reduced PuO₂ (PuO_2-x) as functions of environmental temperature and partial pressure of oxygen, which shows fairly agreement with corresponding high-temperature experiments. Under ambient conditions, the endothermic reduction of PuO₂ to α-Pu₂O₃ is found to be facilitated by accompanying volume expansion of PuO_2-x and the possible migration of O-vacancy, whereas further reduction of α-Pu₂O₃ is predicted to be much more difficult. In contrast to the endothermic oxidation of PuO₂, the oxidation of α-Pu₂ O₃ is a stable exothermic process.

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