Study on the Electrochemical Behaviors of CeO₂ in Eutectic CaCl₂ – NaCl Melt

Abstract:

The electro–reduction of CeO₂ in eutectic CaCl₂–NaCl melt was studied by cyclic voltammetry and constant voltage electrolysis techniques. One cathodic current peak in the cyclic voltammogram was observed and supports a one–step electro–reduction mechanism of CeO₂. During different times of electrolysis at 800°Cof temperature and 3.0V of constant voltage, the products CeOCl and CeO₂ were observed by XRD and confirms the following electro–reduction sequence: CeO₂CeOCl.

• Periodical: Advanced Materials Research (Volumes 284-286)
• Pages: 2114-2118
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.284-286.2114
• Online since: July 2011
• Authors: Pyong Hun Kim, Hong Wei Xie, Yu Chun Zhai, Su Hong Ji
• Keywords: CeO₂, Electroreduction, Mechanism

References

[1] J.A. Plambeck, in: A.J. Bard (Ed.), Encyclopedia of Electrochemistry of the Elements, Volume X, Fused Salt Systems, Marcel Dekker, New York, 1976.

[2] Y.Castrillejo, M.R. Bermejo, R.Pardo, A.M. Martinez, Use of electrochemical techniques for the study of solubilization processes of cerium-oxide compounds and recovery of the metal from molten chlorides. J. Electroanal. Chem. 522(2002) 124-140.

DOI: 10.1016/s0022-0728(02)00717-9

[3] B.J. Zhao, L.Wang, L. Dai ,G.H. Cui, H.Z. Zhou, R.V. Kumar, Direct electrolytic preparation of cerium/nickel hydrogen storage alloy powder in molten salt. J. Alloys Compd. 468(2009) 379-385.

DOI: 10.1016/j.jallcom.2008.01.074

[4] B.J. Zhao, X.G. Lu ,Q.D. Zhong ,C.H. Li ,S.L. Chen, Direct electrochemical preparation of CeNi5 and LaxCe1-xNi5 alloys from mixed oxides by SOM process. Electrochim. Acta 55 (2010) 2996-3001.

DOI: 10.1016/j.electacta.2010.01.008

[5] G. Picard, Y. Mottot, B. Tremillon, in: Proceedings of the 5th International Symposium Molten Salts. The Electrochemical Society Softbound Proceedings Series, 1986, vol. 86, p.189.

[6] X. Kang, Q. Xu, X.M. Yang, Q.S. Song, Electrochemical synthesis of CeNi4Cu alloy from the mixed oxides and in situ heat treatment in a eutectic LiCl-KCl melt. Mater. Lett. 64(2010) 2258-2260.

DOI: 10.1016/j.matlet.2010.07.007

[7] J. Wang, A. Pisch, R. Flukiger, J.L. Jorda, Phase equilibrium in the cerium-poor Ce-Ni-Cu system. J. Alloys. Compd 436(2007)161-169.

DOI: 10.1016/j.jallcom.2006.11.012

[8] J.Dischinger, H.J. Schaller, On the constitution and thermodynamics of Ni-La alloy. J.Alloys. Compd.312(2000)201-210

DOI: 10.1016/s0925-8388(00)01151-8

[9] B.Y. Yuan, T.H. Okabe, Niobium powder production by reducing electrochemically dissolved niobium ions in molten salt. J. Alloy. Compd. 454(2008)185-193.

DOI: 10.1016/j.jallcom.2006.12.121

[10] Y. Mottot, Doctoral Thesis, Paris, 1986.

[11] P. Kar, J.W. Evans, A model for the electrochemical reduction of metal oxides in molten salt electrolytes. Electrochim. Acta 54(2008)835-843.

DOI: 10.1016/j.electacta.2008.06.040

[12] K. Jiang, X.H. Hu, H.J. Sun, D.H. Wang, X.B. Jin, Y.Y. Ren, G.Z. Chen, Electrochemical synthesis of LiTiO2 and LiTi2O4 in molten LiCl. Chem. Mater.16 (2004) 4324-4329.

DOI: 10.1021/cm0494148