YF_(3)-LiF熔盐中Y(Ⅲ)的电化学行为研究  

Study on Electrochemical Behavior of Y(Ⅲ) in Molten YF_(3)-LiF

作　　者：黄海涛 于兵 闫奇操[1,2] 陈国华 张全军 刘玉宝[1,2] HUANG Hai-tao;YU Bing;YAN Qi-cao;CHEN Guo-hua;ZHANG Quan-jun;LIU Yu-bao(State Key Laboratory of Bayan Obo Rare Earth Resource Research and Comprehensive Utilization,Baotou 014030,China;Baotou Research Institute of Rare Earths,Baotou 014030,China)

机构地区：[1]白云鄂博稀土资源研究与综合利用国家重点实验室,内蒙古包头014030 [2]包头稀土研究院,内蒙古包头014030

出　　处：《稀有金属与硬质合金》2021年第3期5-8,23,共5页Rare Metals and Cemented Carbides

摘　　要：利用循环伏安法研究了YF_(3)-LiF熔盐体系中Y(Ⅲ)的电化学还原过程以及Y_(2)O_(3)的阴极行为。结果表明:Y(Ⅲ)在YF_(3)-LiF熔盐钼电极上的还原电位为-0.95 V(vs.Pt),反应为一步转移三电子的准可逆反应。氧化还原峰不随扫描速度而改变,说明该反应是可逆程度很大的准可逆反应,v^(1/2)与峰电流Ip呈线性关系,反应受扩散控制,扩散系数为3.626 4×10^(-8) cm^(2)/s。Y_(2)O_(3)加入熔盐中有助于Y(Ⅲ)还原电位的降低,有一定的去极化作用。Y(Ⅲ)在铁电极上的还原过程出现了三个不同的还原电流峰,发生欠电位沉积形成钇铁合金相,电还原生成金属钇。The electrochemical reduction process of Y(Ⅲ) and the cathode behavior of Y_(2)O_(3) in YF_(3)-LiF molten salt system were studied by cyclic voltammetry.The results indicate that the reduction potential of Y(Ⅲ) on molybdenum electrode is-0.95 V(vs.Pt) in YF3-LiF molten salt system, and the reaction is a quasi reversible reaction that transfers three electrons in one step.The redox peak does not change with the scanning speed, which indicates that the reaction is a quasi reversible reaction with great reversibility.The peak current Ip is linearly related to v^(1/2),so the reaction is controlled by diffusion with diffusion coefficient of 3.626 4×10^(-8) cm^(2)/s.The addition of Y_(2)O_(3) into molten salt contributes to reducing reduction potential of Y(Ⅲ) and has a certain depolarization effect.There are three different reduction current peaks in the reduction process of Y(Ⅲ) on the iron electrode.Yttrium-iron alloy phase is formed by underpotential deposition and yttrium metal is formed by electroreduction.

关 键 词：氧化钇 氧化还原 钇铁合金 循环伏安法 扩散控制 

分 类 号：O646.541[理学—物理化学]