【摘要】 本文研究了铕（Ⅲ）在Nafion聚合物薄膜化学修饰电极上的电化学行为。研究结果表明,在pH5.8的醋酸缓冲溶液中,铕（Ⅲ）的氧化还原非常接近可逆过程。利用二甲酚橙的络合作用和Nafion的阳离子交换作用,在选定条件下,铕（Ⅲ）的导数波高度与其浓度在2.0×10^-7～1.0×10^-5mol/L范围内成线性关系,检出限为1.0×10^-7mol/L。当富集时间为10min时,检出限可达2.0×10^-8mol/L,Sm（Ⅲ）、Yb（Ⅲ）及其他稀土元素基本不干扰,可用于铕（Ⅲ）的分析测定。同时避免了使用汞（Ⅱ）的问题。更多还原

【Abstract】 Electrochemical behaviour of Eu（Ⅲ） at a Nafion polymer film electrode was studied by using cyclic voltammetry. The result showed that the electrochemical reaction of Eu（Ⅲ） in acetic buffer solution （pH 5.8） at a Nafion film electrode is nearly a reversible process. A sensitive stripping voltammetry method for the determination of Eu（Ⅲ） was proposed in the presence of xylenol orange （XO） as a ligand at the Nafion film electrode. In the solution of 0.1mol/L HAc-NaAc （pH2.9） containning 1.0×10^-4mol/L of XO, cathodic scanning from -0.2 to -1.5V, （vs. SCE） at sweep rate of 200mV/s after 1 min at-0.2V, the reduction wave of Eu（Ⅲ）-XO at about -1.2V was recorded, The peak current is proportional to the concentration of Eu（Ⅲ） in the range of 2.0×10^-7～1.0×10^-5 mol/L with a detection limit of 1.0×10^-7mol/L. When the accumulated time at -0.2 V was increased to 10min, the detection limit was below 2.0×10^-8 mol/L. No interferences of Sm（Ⅲ）, Yb（Ⅲ） and other rare earth ions were observed. And the mercury pollution in the method could be avoided.更多还原