銅及銀在1-丁基-3-甲基咪唑水楊酸根離子液體中電化學與電沉積研究

Electrochemical study and electrodeposition of copper and silver in 1-butyl-3-methylimidazolium salicylate ionic liquid

張宇廷(Yu-Ting Chang)

指導教授 ： 陳泊余

高雄醫學大學/生命科學院/醫藥暨應用化學研究所/碩士(2012年)

摘要

本論文根據文獻以salicylate sodium salt為陰離子來源，1-butyl-3-methylimidazolium chloride為陽離子來源混合而成1-butyl-3-methylimidazolium salicylate 離子液體，並在此離子液體中探討Cu(I)、Cu(II)及Ag(I)的電化學行為、電沉積和鍍層性質的探討。
在此離子液體中，Cu(I)來源為添加CuCl或陽極電解銅絲的方式產生，Cu(II)的來源為添加CuCl2，或是先電解銅絲產生Cu(I)再用Pt片當工作電極轉成Cu(II)，並探討不同溫度下的影響。至於銀離子的來源亦是採用添加AgCl或是電解銀絲而獲得。之後分別利用玻璃碳電極和白金電極探討這些金屬離子在此離子液體中的電化學行為。接著以鐵絲和銅絲為銅及銀的電沉積基材，並將所沉積的樣品利用掃描式電子顯微鏡(scanning electron microscope，SEM)和能量分散光譜儀(energy dispersive spectrometer，EDS)觀察鍍層表面組成型態和元素半定量分析。
最後分別將電沉積的銅和銀修飾電極在1M的NaOH溶液中對硝酸根離子還原反應進行測試。先使用循環伏安法，之後再進一步利用amperometric i-t curve的方式進行硝酸根離子回收率的測試。實驗結果顯示硝酸根離子還原電流與濃度間的線性範圍為0.49~5.22 mM，回收率為109%(±0.02)。

關鍵字

離子液體

並列摘要

In this thesis, the electrochemical behaviors, electrodeposition, and coating properties of Cu(I)、Cu(II) and Ag(I) were investigated in 1-butyl-3-methylimidazolium salicylate ionic liquid (BMI-SAL IL). The Cu(I) species was introduced into the IL by the addition of CuCl or the anodic dissolution of a copper electrode. The Cu(II) species was attained by adding CuCl2 or using Pt foil as working electrode to oxidize Cu(II). The effect of the temperature on the electrochemical behavior was also studied. The same methods were employed to introduce Ag(I) species into the IL except AgCl and a silver electrode were used. Glassy carbon and platinum electrodes were also applied to further study the electrochemical behaviors of those in IL. Then, iron and copper wires, as substrates, were coated with copper and silver respectively to be tested further by controlled-potential electrolysis. The surface morphology and composition of all the electrodeposition samples were analyzed by scanning electron microscope (SEM) and energy dispersive spectrometry (EDS), respectively.
The final part is to study the electrocatalytic reduction of nitrate in 1M NaOH by using these modified electrodes. Cyclic-voltammetry was applied first, then went on with amperometric i-t curve. The result showed the dependence of cathodic peak current of nitrate reduction on the concentration nitrate was linear from 0.49~5.22 mM(R2=0.9993) and the recovery was 109%(±0.02).

並列關鍵字

ionic liquid

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