耿 傲,何几文,刘 欢,华中胜,张梦龙,徐 亮.NaCl-KCl-NdCl3-AlCl3熔盐体系电解制备Nd-Al合金及机理 [J].稀有金属材料与工程,2020,49(7):2462~2469.[Geng Ao,He Jiwen,Liu Huan,Hua Zhongsheng,ZHang Menglong,Xu Liang.Preparation and Reaction Mechanism of Nd-Al Alloys by Electrolysis in Molten NaCl-KCl-NdCl3-AlCl3[J].Rare Metal Materials and Engineering,2020,49(7):2462~2469.]
NaCl-KCl-NdCl3-AlCl3熔盐体系电解制备Nd-Al合金及机理
投稿时间:2019-06-19  修订日期:2019-06-28
中文关键词:  [sub_s][sub_e][sub_s]:[sub_e] [sub_s]熔盐电解[sub_e][sub_s]  Nd-Al[sub_e][sub_s]合金[sub_e][sub_s]  [sub_e][sub_s]电化学行为[sub_e][sub_s]  [sub_e][sub_s]金属间化合物[sub_e][sub_s]  [sub_e][sub_s]欠电位沉积[sub_e]
基金项目:国家自然科学基金项目(面上项目,重点项目,重大项目)
中文摘要:
      在700℃的NaCl-KCl体系中,采用循环伏安法、方波伏安法和开路计时电位法等电化学测试方法研究了钨电极上Nd(III)的电化学行为以及与Al(III)共沉积的电化学过程。结果表明:在低扫描速率(0.1~0.5V.s-1)下,NaCl-KCl-NdCl3熔盐中Nd(III)的还原是一步交换三个电子的准可逆过程,该还原过程由扩散步骤控制,扩散系数约为7.6×10-5cm2.s-1。将AlCl3引入NaCl-KCl-NdCl3熔体后,循环伏安、方波伏安以及开路计时电位测试结果表明电解过程中形成了三种Nd-Al金属间化合物(Nd3Al11、NdAl3和NdAl2),其形成机理为Nd在预先沉积的Al上发生欠电位沉积。通过电动势法,计算了700℃时Nd-Al金属间化合物的热力学参数,如两相共存下Nd的活度和相对偏摩尔吉布斯自由能以及Nd-Al金属间化合物的标准吉布斯自由能。在-2.3V下进行恒电位电解5h得到Nd-Al合金,物合金由金属间化合物Nd3Al11、NdAl3、NdAl2和纯Al组成。
Preparation and Reaction Mechanism of Nd-Al Alloys by Electrolysis in Molten NaCl-KCl-NdCl3-AlCl3
英文关键词:molten salt electrolysis  Nd-Al alloys  electrochemical behavior  intermetallic compounds  underpotential deposition
英文摘要:
      : The electrochemical behaviors of Nd(III) on tungsten electrode and its co-deposition with Al(III) in NaCl-KCl salts at 700 °C were investigated by a series of electrochemical techniques such as cyclic voltammetry, square wave voltammetryand open-circuit chronopotentiometry, and thus Nd-Al alloy was prepared via direct co-deposition of Nd and Al on the inert electrode. The results show thatthe reduction of Nd(III) in NaCl-KCl-NdCl3 melts isa one-step process with three electrons exchanged, and the reaction is anirreversible processcontrolled by diffusionat low scan rate (0.1~0.5V/s) with the calculated diffusion coefficient is approximately 7.6×10-5cm2/s. After AlCl3introduced into the NaCl-KCl-NdCl3 melts, the curves of cyclic voltammetry, square wave voltammetryand open-circuit chronopotentiometry indicate that three kinds of Nd-Al intermetallic compounds (Nd11Al3, NdAl3 and NdAl2) were formed. It can be deduced that the underpotential deposition of Nd occurs on the tungsten electrode covered with the pre-deposited metal Al from the open circuit chronopotentiometriy. Based on the results of open circuit chronopotentiometriy, the thermodynamic properties of Nd-Al intermetallic compounds were determined by electromotive force measurement at 700 °C, such as the activity of Nd in two-phase coexisting state and relative partial molar Gibbs energies, as well as the standard Gibbs energies ofNd-Al intermetallic compound. Finally, potentiostatic electrolysis was carried out at -2.3Vfor 5h to obtain a product alloys. X-ray diffraction (XRD) and scan electron micrograph (SEM)-energy dispersive spectrometry (EDS) analysis indicated that the obtained alloys were mainly composed of Nd11Al3, NdAl3, NdAl2 and Al phases.
作者单位E-mail
耿 傲 安徽工业大学冶金工程学院 ahutga@126.com 
何几文 安徽工业大学冶金工程学院  
刘 欢 安徽工业大学冶金工程学院  
华中胜 安徽工业大学冶金工程学院  
张梦龙 安徽工业大学冶金工程学院  
徐 亮 安徽工业大学冶金工程学院  
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