物理化学学报 >> 2015, Vol. 31 >> Issue (2): 309-314.doi: 10.3866/PKU.WHXB201412182

电化学和新能源 上一篇    下一篇

Dy(Ⅲ)离子在LiCl-KCl熔盐中的电化学行为及Dy-Ni金属间化合物的选择性制备

李梅1, 孙婷婷2, 刘斌1, 韩伟1, 孙扬1, 张密林1   

  1. 1. 哈尔滨工程大学材料科学与化学工程学院, 教育部超轻材料与表面技术重点实验室, 哈尔滨 150001;
    2. 齐齐哈尔工程学院建筑工程系, 黑龙江 齐齐哈尔 161005
  • 收稿日期:2014-10-27 修回日期:2014-12-17 发布日期:2015-01-26
  • 通讯作者: 韩伟 E-mail:weihan@hrbeu.edu.cn
  • 基金资助:

    国家自然科学基金(21271054, 21173060),国家自然科学基金重大研究计划(91326113, 91226201)和中央高校基本科研业务经费(HEUCF201403001)资助

Electrochemical Behavior of Dy(Ⅲ) and the Selective Formation of Dy-Ni Intermetallic Compounds in LiCl-KCl Eutectic Melts

LI Mei1, SUN Ting-Ting2, LIU Bin1, HAN Wei1, SUN Yang1, ZHANG Mi-Lin1   

  1. 1. Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, P. R. China;
    2. Department of Construction Engineering, Qiqihar Institute of Engineering, Qiqihar 161005, Heilongjiang Province, P. R. China
  • Received:2014-10-27 Revised:2014-12-17 Published:2015-01-26
  • Contact: HAN Wei E-mail:weihan@hrbeu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21271054, 21173060), Major Research Plan of the National Natural Science Foundation of China (91326113, 91226201), and Fundamental Research Funds for the Central Universities, China (HEUCF201403001).

摘要:

采用循环伏安、方波伏安和开路计时电位等电化学方法研究了Dy(Ⅲ)离子在LiCl-KCl 共晶盐中的电化学行为及Dy-Ni 合金形成的电化学机理. 循环伏安和方波伏安法研究表明, Dy(Ⅲ)离子的电化学还原过程为三个电子转移的一步反应. 与惰性W电极相比, Dy(Ⅲ) 离子在Ni 电极上的循环伏安曲线多出了三对氧化还原峰,是由于Dy与Ni 形成了合金化合物, 导致Dy(Ⅲ)离子在活性Ni 电极发生了欠电位沉积. 采用X射线衍射(XRD)和扫描电子显微镜(SEM)附带能量散射谱(EDS)对恒电位(-1.6, -1.8 和-2.0 V)电解制备的Dy-Ni 合金进行分析, 分别获得了DyNi5, Dy2Ni7和DyNi2金属间化合物. 实验结果表明, 通过控制电位进行恒电位电解可以有选择性地制备不同的金属间化合物.

关键词: Dy-Ni 金属间化合物, 电化学行为, 氯化物熔盐, 恒电位电解, 镍电极

Abstract:

The electrochemical behavior of Dy(Ⅲ) in LiCl-KCl melts and the alloying mechanism of Dy-Ni alloys were investigated by cyclic voltammetry, square wave voltammetry, and open circuit chronopotentiometry. Cyclic voltammetry and square wave voltammetry experiments indicated that the reduction of Dy(Ⅲ) ions to Dy metal occurred in a single step with the exchange of three electrons. Compared with cyclic voltammograms on an inert W electrode, three reduction peaks are observed. This indicates the under-potential deposition of Dy(Ⅲ) on a reactive Ni electrode because of the formation of Dy-Ni alloy compounds. Dy-Ni alloys were prepared by potentiostatic electrolysis at -1.6, -1.8, and -2.0 V and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS). The results confirm that different Dy- Ni compounds: DyNi5, Dy2Ni7, and DyNi2 can be selectively obtained by potentiostatic electrolysis at different potentials.

Key words: Dy-Ni intermetallic compound, Electrochemical behavior, Molten chloride, Potentionstatic electrolysis, Ni electrode

MSC2000: 

  • O646