α-Ni(OH)2 electrodeposition from NiCl2 solution  

从氯化镍溶液中电沉积α-Ni(OH)2

作　　者：Jun-jie ZHANG Ting-an ZHANG Sen FENG 张俊杰;张廷安;冯森(东北大学冶金学院,沈阳110819;东北大学多金属共生矿生态冶金教育部重点实验室,沈阳110819)

机构地区：[1]School of Metallurgy,Northeastern University,Shenyang 110819,China [2]Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education,Northeastern University,Shenyang 110819,China

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第10期2802-2811,共10页中国有色金属学报（英文版）

基　　金：Project(U1710257)supported by the National Natural Science Foundation of China。

摘　　要：α-Ni(OH)2 was synthesized from a NiCl2 solution by electrodeposition method.In order to conduct a systematic study on the effects of experimental parameters,a series of electrolyte initial pH values,current densities,electrodeposition temperatures,and electrodeposition time were used.Cyclic voltammetry results demonstrated a side reaction of Ni^2++2e→Ni.The X-ray diffraction analysis,Fourier-transform infrared spectrum,and the color of the product showed that pureα-Ni(OH)2 could be obtained in the initial pH value range of 2−5.86,current density range of 10−25 mA/cm^2,electrodeposition temperature range of 25−35℃,and electrodeposition time range of 1.0−3.0 h.When electrodeposition temperature increased to 45℃,a mixture ofα-Ni(OH)2 and metallic Ni was obtained.A current density higher than 30 mA/cm^2 resulted in the sample with features ofβ-Ni(OH)2.A small amount of metallic Ni existed in the as-prepared sample when current density decreased to 5 mA/cm^2.A slight increase of electrolyte pH was observed with increasing initial solution pH and current density.Electrodeposition mass revealed a slight decrease with initial pH decreasing and showed an almost linear increase with current density increasing.The slope of the curve for electrodeposition mass versus electrodeposition time remained stable in the first 2.0 h and then decreased.采用电沉积方法从NiCl2溶液中合成α-Ni(OH)2。为了系统地研究实验条件的影响,选用一系列初始NiCl2溶液pH值、电流密度、电沉积温度和电沉积时间。循环伏安结果表明,存在副反应:Ni^2++2e→Ni。从X射线衍射光谱分析、傅里叶红外光谱分析以及产物的颜色可知,当电解液初始pH为2~5.86、电流密度为10~25 mA/cm^2、电沉积温度为25~35℃以及电沉积时间为1.0~3.0 h时,电沉积产物为纯净的α-Ni(OH)2。当沉积温度升高至45℃时,获得的产物为α-Ni(OH)2和金属Ni的混合物;当电流密度超过30 mA/cm^2时,获得产物呈β-Ni(OH)2的特征;当电流密度低至5 mA/cm^2时,产物中有少量的金属Ni。电解液的pH随溶液的初始pH和电流密度的增加略微增加;产物的沉积质量随初始pH降低略微减小,随着电流密度的增加近乎线性增加。沉积质量−沉积时间曲线的斜率在起初的2.0 h内保持恒定,随后降低。

关 键 词：Α-NI(OH)2 NiCl2 ELECTRODEPOSITION electrolyte initial pH current density electrodeposition temperature electrodeposition time 

分 类 号：TQ138.13[化学工程—无机化工]