工业电解液中镍阴极沉积和阳极溶出过程的EQCM研究  

EQCM of Nickel Cathode Deposition and Anode Dissolution in Industrial Electrolyte

作　　者：徐仰涛[1,2,3] 黄凯 朱珍旭[1,2,3] XU Yang-tao;HUANG Kai;ZHU Zhen-xu(State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metal under the Province and the Ministry of Education,Lanzhou University of Technology,Lanzhou 730050,China;School of Materials Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China;State Key Laboratory of Nickel and Cobalt Resources Comprehensive Utilization,Jinchang 737100,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050 [2]兰州理工大学材料科学与工程学院,兰州730050 [3]镍钴资源综合利用国家重点实验室,甘肃金昌737100

出　　处：《表面技术》2019年第9期293-299,314,共8页Surface Technology

基　　金：镍钴资源综合利用国家重点实验室资助~~

摘　　要：目的通过电极表面质量的变化对工业电解液中Ni阴极沉积和阳极溶出过程进行研究,同时考察温度对此过程的影响。方法采用循环伏安法(CV)研究硫化镍可溶阳极/混酸体系的工业电解液中,镍在金电极表面的阴极沉积、阳极溶出过程以及温度对该过程的影响,并利用电化学石英晶体微天平(EQCM)技术对此过程中电极表面的频率响应进行实时监测,同时依据实验测定的M/n值对此过程中不同电位区间的电极过程进行研究。结果电解液温度为30℃时,Ⅰ和Ⅱ沉积区的M/n值分别为30.8、29.3g/mol,与之对应的Ⅲ-1和Ⅲ-2溶出区的M/n值分别为30.7、29.4g/mol。改变实验温度后,20℃时循环伏安实验将无法正常进行,当电解液温度由20℃逐步升高至25、30、35℃时,归属于沉积峰的M/n值依次为30.3、30.9、26.3g/mol。随着温度的升高,镍的起始沉积电位逐渐正移,阴极沉积过程进行完全时,随着温度的升高,沉积在电极表面的镍沉积层质量逐渐增加,阳极溶解完全后,残留在电极表面的镍沉积层质量逐渐减少。结论工业电解液中与镍沉积电位相近的金属离子(Co^2+、Cu^2+)与Ni^2+发生共同沉积,并且种类随着温度的升高趋于复杂化。适当提高电解液的温度不仅有利于CV曲线中“形核环”和“溶出峰”的出现,而且还有助于镍的沉积,但同时也会形成结构疏松且易于溶解的沉积层。在-1.4V时,CV曲线电位扫描方向的转变,使得沉积层结构发生变化,导致溶出过程发生分区溶解,并且溶出过程的分区现象随着温度的升高而越发明显。The work aims to study the cathode deposition and anode dissolution of Ni in industrial electrolyte through the change of electrode mass and investigate the effect of temperature on this process.Cyclic voltammetry (CV) was used to study the cathodic deposition and anodic dissolution process of nickel on gold electrodes in industrial electrolytes of nickel sulfide soluble anode/mixed acid system and the effect of temperature on this process.Electrochemical quartz crystal microbalance (EQCM) was applied to monitor the frequency on electrode surface during this process in real time.At the same time,the electrode process in different potential range was analyzed according to M/n determined by experiment.When the electrolyte temperature was 30 ℃,the M/n values of the Ⅰ and Ⅱ deposition zones were 30.8 and 29.3 g/mol,respectively,and the M/n values of the Ⅲ-1 and Ⅲ-2 dissolution zones were 30.7 and 29.4 g/mol,respectively.After the experiment temperature was changed to 20 ℃,cyclic voltammetry could not be conducted.When the temperature of the electrolyte was gradually increased from 25 ℃ to 30 ℃ and 35 ℃,the M/n values of the deposition peaks were 30.3,30.9 and 26.3 g/mol,respectively,As the temperature increased,the initial deposition potential of nickel was positively shifted.During cathode deposition,the mass of nickel disposition layer on electrode surface gradually increased with the increasing temperature.After anode dissolution,the mass of nickel disposition layer on electrode surface gradually decreased.Metal ions (Co^2+,Cu^2+) close to the nickel ion in deposition potential will co-deposit with Ni^2+,and types tend to be complicated with increasing temperature.Properly increasing the temperature of the electrolyte not only facilitates the deposition of nickel,but also promotes the appearance of nucleation rings and dissolution peaks in CV curves.Besides,the deposition with loose structure and soluble properties can be formed.The change in the direction of potential scanning in the CV curve re

关 键 词：镍 电解液 电结晶 阴极沉积 阳极溶出 EQCM 镀镍 镍电解 

分 类 号：TG174.44[金属学及工艺—金属表面处理] TQ153.12[金属学及工艺—金属学]