类离子液体电沉积制备镁镍及锌镍合金的研究

发布时间：2018-03-08 08:04

本文选题：类离子液体　切入点：镁镍合金　出处：《昆明理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：镍合金作为一种重要的战略性材料,在储氢性能和防腐性能领域有着极其重要的研究意义。电沉积法是制备镍合金的一种重要方法,传统的镍合金电镀主要是在含无机盐的水溶液体系中进行的,但普遍存在工艺复杂、成本高等问题。类离子液体作为一种新型的绿色溶剂,其具备电化学窗口宽、液态温度范围大、无析氢反应等优良特点,是电沉积镍合金的优良电解液。本文采用成本低廉、合成简单的苄基三乙基氯化铵-丙三醇-氯化镍-氯化镁(TEBAC-GL-NiCl_2-MgCl_2)类离子液体和氯化胆碱-尿素-乙二醇-氧化镍-氧化锌(ChCl-urea-EG-Ni_2O_3-ZnO)类离子液体作为电解质,进行电沉积制备镁镍合金和锌镍合金的研究实验。采用TEBAC-GL-NiCl_2-MgCl_2类离子液体为电解液,以铜片为阴极、石墨片为阳极,成功地制备出了颗粒尺寸均匀且镀层致密平整的镁镍合金镀层。采用循环伏安法、计时电流法等多种电化学测试手段,系统地研究了 Ni和Mg-Ni合金在该体系中的电沉积行为,并运用XRF、XRD、SEM等检测手段对镀层的成分、形貌进行分析。结果表明:随着温度的升高,该类离子液体的电导率显著增大;在TEBAC-GL-NiCl_2体系中加入MgCl_2后,循环伏安曲线中的还原电流明显增大,表明可能实现Mg和Ni的共沉积;当Mg~(2+)浓度为0.005mol/L,Ni~(2+)浓度为0.1mol/L时,在塔菲尔曲线中Mg和Ni的平衡电位差值最小,为1.2532V;以玻碳电极为工作电极时,Ni和Mg-Ni合金在类离子液体中的电沉积属于三维瞬时形核模型;当槽电压为2.3V、温度为353K、镁离子和镍离子摩尔浓度均为0.1 mol·L~(-1)时,沉积层中镁的含量最高,其质量分数为12.13%。采用ChCl-urea-EG-Ni_2O_3-ZnO类离子液体为电解液,在以镀铜铁片为工作电极、铂电极为对电极、高纯银丝为参比电极的三电极体系中,采用恒电位电沉积制备出了颗粒尺寸均匀且镀层致密平整的Zn-Ni合金镀层。采用循环伏安法、塔菲尔曲线测试等多种电化学测试手段,系统地研究了 Ni、Zn和Zn-Ni合金在该体系中的电沉积行为,并运用XRF、XRD、SEM等检测手段对镀层的成分、形貌进行分析。结果表明:Ni(Ⅱ)的加入导致ChCl-urea-EG-ZnO体系中循环伏安曲线的起始还原电位正移,形核过电位增大,在正扫的过程中Zn的氧化峰发生了正移,因此,形成了锌镍合金;温度为353K、Ni_2O_3为5g/L、ZnO为2g/L,沉积电位为-1.3V时,可以得到耐腐蚀性能相对最好的Zn0.85Ni0.15合金镀层;在-1.3V沉积得到的Zn0.85Ni0.15合金的腐蚀电流最小,为0.4μA/cm2,腐蚀电位为-934mV,其耐腐蚀性能最好;Zn0.85Ni0.15合金镀层在Nyquist图谱的高频区表现出最大的容抗弧半圆直径,由于其具有最大的R_(ct),因此其具有最高的极化电阻。
[Abstract]:As an important strategic material, nickel alloy is of great significance in the field of hydrogen storage and corrosion resistance. Electrodeposition is an important method for the preparation of nickel alloy. Traditional nickel alloy electroplating is mainly carried out in aqueous solution system containing inorganic salt, but the process is complex and the cost is high. As a new kind of green solvent, ionic liquid has wide electrochemical window. Due to its wide range of liquid temperature and no hydrogen evolution reaction, it is an excellent electrolyte for electrodeposition of nickel alloy. Synthesis of simple benzyl triethylammonium chloride, propanetriol, nickel chloride, magnesium chloride, TEBAC-GL-NiCl2-MgCl _ 2) ionic liquids and choline chloride, urea-glycol, nickel oxide, zinc oxide, chCl-urea-EG-Ni2O3-ZnO ionic liquids as electrolytes, The preparation of magnesium-nickel alloy and zinc-nickel alloy by electrodeposition was studied. TEBAC-GL-NiCl_2-MgCl_2 ionic liquid was used as electrolyte, copper as cathode and graphite as anode. The electrodeposition behavior of Ni and Mg-Ni alloys in this system has been systematically studied by cyclic voltammetry and chronoamperometric method, and the electrodeposition behavior of Ni and Mg-Ni alloys in this system has been systematically studied by means of cyclic voltammetry and chronoamperometry. The composition and morphology of the coating were analyzed by means of X-ray diffraction SEM. The results showed that the conductivity of this kind of ionic liquids increased significantly with the increase of temperature, and MgCl_2 was added to the TEBAC-GL-NiCl_2 system. The reduction current in the cyclic voltammetry curve is obviously increased, which indicates that the codeposition of mg and Ni is possible, and when the concentration of Mg~(2 is 0.005 mol / L, the equilibrium potential difference between mg and Ni is the smallest in the Taffel curve, when the concentration of Mg~(2 is 0.005 mol / L, and the concentration of Ni is 0.1 mol / L, the equilibrium potential difference between mg and Ni in the Taffel curve is the smallest. Using glassy carbon electrode as working electrode, the electrodeposition of Ni and Mg-Ni alloys in ionic liquids belongs to a three-dimensional instantaneous nucleation model, when the cell voltage is 2.3 V, the temperature is 353K, and the molar concentrations of magnesium and nickel ions are 0.1 mol 路L ~ (-1), respectively. The content of magnesium in the deposit layer is the highest, the mass fraction of which is 12.13.The ChCl-urea-EG-Ni_2O_3-ZnO ionic liquid is used as electrolyte, in the three-electrode system with copper plating iron sheet as working electrode, platinum electrode as opposite electrode, and high purity silver wire as reference electrode, The Zn-Ni alloy coating with uniform particle size and dense and flat coating was prepared by potentiostatic electrodeposition, and many electrochemical methods, such as cyclic voltammetry and Taffel curve test, were used. The electrodeposition behavior of Nianzn and Zn-Ni alloys in this system was systematically studied, and the composition of the coating was examined by means of XRF, XRD, SEM and so on. The results showed that the initial reduction potential of cyclic voltammetry curve in ChCl-urea-EG-ZnO system was positively shifted, the nucleation overpotential increased, and the oxidation peak of Zn occurred positive shift in the process of forward sweep. Therefore, the zinc-nickel alloy was formed. At a temperature of 353K / Ni2O3 of 5g / L, with a deposition potential of -1.3V, the Zn0.85Ni0.15 alloy coating with the best corrosion resistance can be obtained, and the Zn0.85Ni0.15 alloy deposited at -1.3V has the lowest corrosion current. The corrosion potential is -934mV, and the corrosion resistance of Zn0.85Ni0.15 alloy coating is the highest in the high frequency region of Nyquist. Because of its maximum RSCT, the alloy coating has the highest polarization resistance. The corrosion potential is -934mV, and the corrosion potential is -934mV. the corrosion resistance of Zn0.85Ni0.15 alloy coating is the highest in the high frequency region of Nyquist.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ153.2

【参考文献】