Rare Metals

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Electrochemical co-reduction of holmium and magnesium ions in eutectic LiCl–KCl salts

  • Ji Wang
  • Mei Li
  • Wei Han
  • Zhi-Yixiong Liu
  • Xiao-Guang Yang
  • Yang Sun
  • Mi-Lin Zhang


The electrochemical co-reduction of Ho(III) and Mg(II) ions was investigated on Mo electrode in eutectic LiCl–KCl salts at temperature of 773 K using various electrochemical techniques. Cyclic voltammogram (CV) and square wave voltammogram exhibit three reduction peaks corresponding to the reduction of Ho(III) on pre-deposited Mg electrode, whose potentials are more positive than that of Ho on Mo electrode because of the formation of Mg-Ho intermetallic compounds by co-reduction of Ho(III) and Mg(II) ions. Meanwhile, chronopotentiometry and open-circuit chronopotentiometry were used to explore the electrochemical formation of Mg–Ho intermetallics. Mg–Ho alloys were produced by galvanostatic electrolysis at the current of 1.5 A for different electrolysis durations. Ho5Mg24, HoMg2 and HoMg intermetallic compounds were acquired and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS). The results indicate that Mg–Ho intermetallic compounds, Ho5Mg24, HoMg2 and HoMg, could be prepared by molten salts electrolysis.


Electrochemical formation Co-reduction Mg–Ho alloys Galvanostatic electrolysis 



This work was financially supported by the National Natural Science Foundation of China (Nos. 11575047, 11675044, 21790373, 21876034 and 11875116), the Major Research Plan of the National Natural Science Foundation of China (Nos. 91326113 and 91226201) and the Fundamental Research Funds for the Central Universities (No. HEUCF201849).


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Copyright information

© The Nonferrous Metals Society of China and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Key Laboratory of Superlight Materials and Surface Technology, College of Material Science and Chemical EngineeringHarbin Engineering UniversityHarbinChina
  2. 2.Institute of Nuclear Energy and SafetyHarbin Engineering UniversityHarbinChina

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