Abstract
We prepared neptunium chloride complexes electrochemically and performed spectroelectrochemical measurements of neptunium ions in LiCl–KCl eutectic melts at 450 °C, where the neptunium concentrations studied were in the range of 0.1–1 mM. We observed a highly absorbing f–d transition band of Np3+ at 383 nm, which was used to determine an formal potential of the Np4+|Np3+ redox couple (E°′ = 0.45 V vs. Ag|Ag+) with a solution of concentration as low as ~0.1 mM. This result agreed well with the value (E°′ = 0.42 V vs. Ag|Ag+) determined by cyclic voltammetry with a ~15 mM solution.
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This work was supported by a National Research Foundation of Korea (NRF) Grant, funded by the Korean government (MSIP) (No. 2012M2A8A5025923).
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Kim, DH., Park, TH., Bae, SE. et al. Electrochemical preparation and spectroelectrochemical study of neptunium chloride complexes in LiCl–KCl eutectic melts. J Radioanal Nucl Chem 308, 31–36 (2016). https://doi.org/10.1007/s10967-015-4321-0
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DOI: https://doi.org/10.1007/s10967-015-4321-0