Pr(III)离子在LiCl-KCl熔体中Bi膜W电极上的电化学行为（英文）  

Electrochemical Behavior of Pr(III) Ions on a Bi-Coated W Electrode in LiCl-KCl Melts

作　　者：姜涛[1] 彭述明[1] 李梅[2] 裴婷婷 韩伟[2] 孙杨[2] 张密林[2] 

机构地区：[1]中国工程物理研究院核物理与化学研究所,四川绵阳621900 [2]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

出　　处：《物理化学学报》2016年第7期1708-1714,共7页Acta Physico-Chimica Sinica

基　　金：The project was supported by the National Natural Science Foundation of China(21271054,11575047,21173060),Major Research Plan of the National Natural Science Foundation of China(91326113,91226201);Fundamental Research Funds for the Central Universities,China(HEUCF201403001)~~

摘　　要：采用循环伏安、方波伏安、计时电位和开路计时电位等电化学方法研究了Pr(III)离子在Li Cl-KCl-Bi Cl_3熔体中W电极上的电化学行为。循环伏安和方波伏安的研究表明,Pr在预先沉积的Bi膜电极上发生欠电位沉积是由于生成了Pr-Bi金属间化合物,导致Pr(III)在Bi膜电极上的还原电位比在W电极上还原电位更正。从开路计时电位曲线可以观察到两相共存的Pr-Bi金属间化合物的两个平台。利用开路计时电位计算了723-873 K温度范围内Pr在Pr-Bi合金中的活度和偏摩尔Gibbs自由能以及Pr-Bi金属间化合物的生成Gibbs自由能。通过恒电位电解,在液态Bi电极上得到了Pr-Bi合金,并采用X射线衍射(XRD)和扫描电子显微镜(SEM)附带能量散射谱(EDS)对样品进行了表征,结果表明所得到的Pr-Bi金属间化合物为Pr Bi_2和Pr Bi。The electrochemical behavior of Pr（III） ions was studied on a Bi-coated W electrode in Li Cl-KCl melts by a series of techniques, such as cyclic voltammetry, square wave voltammetry, and open circuit chronopotentiometry. From the cyclic voltammogram and square wave voltammogram, the underpotential deposition of Pr（III） on pre-deposited Bi（i.e., a Bi-coated W electrode） occurs, owing to the formation of Pr-Bi intermetallic compounds, resulting in the electrochemical reduction of Pr（III） at less cathodic potentials than that on an inert W electrode. Using the open circuit chronopotentiometry technique, two plateaus, corresponding to the co-existence of two phases of Pr-Bi intermetallic compound, were observed. Thermodynamic properties,such as the activities and relative partial molar Gibbs energies of Pr in the Pr-Bi alloys as well as Gibbs energies of the formation for the Pr- Bi intermetallic compounds, were estimated from the open circuit potential measurement in the temperature range of 723-873 K. Pr-Bi alloys were produced on the liquid Bi pool electrode by potentiostatic electrolysis, and were characterized by X- ray diffraction（XRD） and scanning electronic microscopy with energy- dispersive spectrometry（SEM- EDS）. The results indicated that the intermetallic compounds, Pr Bi2 and Pr Bi, were obtained.

关 键 词：电化学行为 Pr-Bi金属间化合物 欠电位沉积 热力学性质 恒电位电解 

分 类 号：O646.54[理学—物理化学]