铜铁试剂修饰碳纤维电极溶出伏安法测定Cu^(2+)  

Determination of Cu^(2+) by Stripping Voltammetry over Cupferron-modified Carbon Fiber Electrode

作　　者：龙彧茵[1] 黎国兰[1] 徐晓梅[1] 张玉枝[1] 李松[1] 

机构地区：[1]绵阳师范学院化学与化学工程学院,四川绵阳621000

出　　处：《绵阳师范学院学报》2013年第8期27-30,34,共5页Journal of Mianyang Teachers＇ College

基　　金：绵阳师范学院校级课题(2013A03)

摘　　要：用铜铁试剂对自制碳纤维电极进行电化学修饰,用于检测溶液中低浓度Cu2+.详细考察了富集电位、富集时间、扫描速度及Cu2+浓度对测定的影响.试验发现在高氯酸溶液中,富集电位-1.2 V,富集时间4 min,Cu2+在0.05 V处有灵敏的阳极溶出峰.试验结果显示Cu2+氧化峰电流在1.0×10-6 mol·L-1至1.0×10-8mol·L-1的范围内呈良好的线性关系,其线性方程:i(nA)=555.2c+47.86(其中c为Cu2+的浓度),线性相关系数R为0.9971,检出限(S/N=3)为8×10-10mol·L-1,平均加标回收率为94.8%,相对标准偏差(RSD)为2.84%(n=6).By using cupferron - modified carbon fiber electrode, a method of anodic - stripping vohammetry for determination of trace Cu2＋ in water was established. In the process of determination, Cu2＋ was firstly pre - concentrated on the surface of carbon fiber electrode modified by cupferron and subsequently reduced to Cu2＋ at - 1.2 V. When the potential of electrode increase from - 0.5 V to 0.5 V, Cu2 ＋ was oxidized and stripped from surface of the electrode, and the sensitive anodic - stripping peak was obtained at 0.05 V. To find the optimal determination conditions, it was investigated that the effect of scanning speed and supporting electrolytes on the elec- trochemical behavior of Cu over the carbon fiber electrode. The most suitable supporting electrolyte is HC104 buffer. The optimal pre - concentration potential and time were - 1.2 V and 4 min respectively. The anodic - strip- ping peaks currents and concentrations showed a good linear relationship in the range of 1.0 × 10 -6 mol · L-1 ＋ 1.0 ＋ 10 -8 mol · L-1 with correlation coefficient （R） of 0. 9971, the standard curve equation was i（nA） = 555.2c ＋ 47.86, and the detection limit （ S/N =3） was 8 × 10 - 10mol · L-1. The average recovery is 94.8% with RSDof2.84 % （n=6）.

关 键 词：铜 铜铁试剂 碳纤维电极 溶出伏安法 

分 类 号：O657.17[理学—分析化学]