以巨孔洞銅電極為模板經電化學置換法製備鉑與鉑-金巨孔洞電極之研究與電化學應用

Fabrication and electrochemical application of macroporous Pt and Pt-Au electrode using galvanic replacement reation on macroporous Cu template

黃舒堅(Shu-Jian Huang)

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

本研究以巨孔洞銅電極為模板，經電化學置換反應製備為巨孔洞鉑與巨孔洞鉑-金電極，並應用於甲醇、乙醇及過氧化氫的電化學偵測。
巨孔洞銅電極為於聚苯乙烯模板的空隙電沉積銅後，將模版移除而得。銅的電沉積分別於水溶液及BMI-SAL (1-butyl-3-methylimidazolium salicylate)、BMP-DCA (N-butyl-N-methylpyrrolidinium dicyanamide)兩種離子液體中達成。以BMP-DCA離子液體中所製備的多層巨孔洞銅電極結構最為優良，因而以其作為模板，置於含H2PtCl6•6H2O或H2PtCl6•6H2O/HAuCl4•3H2O的水溶液中，利用自發性的電化學置換反應製備為巨孔洞鉑或巨孔洞鉑-金電極。置換過程中利用開路電位觀察反應的進行，並探討置換時間與溶液濃度對電極形貌、組成及反應電流的影響。
巨孔洞鉑-金電極相較於巨孔洞鉑電極對甲醇、乙醇具有更好的靈敏度與穩定性。不同比例之金與鉑亦是影響反應性的因素之ㄧ。甲醇、乙醇之氧化電流與濃度間的線性範圍分別為40 μM至2040 μM及10 μM至1820 μM，偵測極限分別為20 μM (s = 3.3 σ) 及10 μM (s = 2.89 σ)。巨孔洞鉑-金電極對過氧化氫的還原亦有較佳的反應性，而抗壞血酸對偵測過氧化氫出現嚴重的干擾，於電極表面修飾Nafion可阻隔部分抗壞血酸的干擾。

關鍵字

巨孔洞銅電極 ； 巨孔洞鉑電極 ； 巨孔洞鉑-金電極

並列摘要

In this study, macroporous Pt and Pt-Au electrodes were fabricated by galvanic replacement on the macroporous Cu templates. These macroporous electrodes were applied to the electrocatalytic oxidation of ethanol, methanol and the electrocatalytic reduction of hydrogen peroxide, respectively.
Macroporous Cu were prepared by electrodeposition of copper from aqueous solution, 1-butyl-3-methylimidazolium salicylate (BMI-SAL) and N-butyl-N-methylpyrrolidinium dicyanamide (BMP-DCA) ionic liquids into the interstitial spaces among the polystyrene (PS) latex spheres that self-assembled onto gold-coated ITO (ITO/Au) electrodes. The macroporous Cu template was immersed in H2PtCl6•6H2O or H2PtCl6•6H2O/HAuCl4•3H2O aqueous solutions in which the galvanic replacement reaction occurred. During the replacement process, open circuit potential (OCP) was monitored to observe the reaction course. In addition, the influence of replacement time and concentration of replacement solutions on the morphology, composition, and activity of the electrodes were also studied.
Macroporous Pt-Au electrode demonstrated the better sensitivity and stability than macroporous Pt electrode towards the oxidation of ethanol and methanol. The steady-state oxidation current linearly depended on the concentration of ethanol or methanol from 10 μM to 1820 μM, or from 40 μM to 2040 μM with the detection limit of 10 μM (s = 2.89 σ) or 20 μM (s = 3.3 σ). Macroporous Pt-Au electrode also presented better activity toward the reduction of hydrogen peroxide. However, it is unfortunate that the interference from ascorbic acid (AA) cannot be avoided, even modified Nafion on the electrode.

並列關鍵字

macroporous Cu ； macroporous Pt ； macroporous Pt-Au electrode

參考文獻

參考文獻

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