碳纳米管修饰电极微分伏安法检测二硝基苯酚异构体  

Electrochemical Analysis of Dinitrophenol Isomers Using Carbon Nanotube Modified Electrode

作　　者：王晓岗 吴庆生[1] 樊雅娟[1] 

机构地区：[1]同济大学化学系,上海200092

出　　处：《应用化学》2008年第6期642-646,共5页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金(20471042);教育部博士点基金(20040247045)资助项目

摘　　要：研究了二硝基苯酚异构体在碳纳米管修饰玻碳电极上的电化学行为。在pH=5．0、0．1mol／L NaAc-HAc缓冲体系中，2，4-二硝基苯酚和2，5-二硝基苯酚在碳纳米管修饰电极上出现灵敏的硝基还原峰，其中2，4-二硝基苯酚分子中四位硝基的还原峰和2，5-二硝基苯酚分子中五位硝基的还原峰显示出明显差异，二者峰电位差达180mV。采用线性扫描方法测定二硝基苯酚混合物的还原电流，并通过半微分处理技术进一步提高还原信号的分离度，实现了2，4-二硝基苯酚和2，5-二硝基苯酚异构体的电化学同时检测。在浓度为1．0×10^-6～5．0×10^-mol／L范围内,2种物质的半微分还原电流与浓度呈线性关系，检测限分别为2．1×10^-7和1．1×10^-7mol／L。对模拟水样进行测定，回收率为97．6％～103．3％。In a 0. 1 mol/L NaAc-HAc buffer solution （ pH = 5.0）, the electrochemical behavior of 2,4- and 2,5-dinitrophenol was investigated at the glassy carbon electrode modified with multi walled carbon nanotube. Each of them exhibited sensitive reduction responses of nitryls. It was found that the reduction peak of nitryl of the position 4-nitrate group of 2,4-dinitrophenol showed great difference from that of the position 5-nitrate group of 2,5-dinitrophenol. The difference between the two reduction potentials was as large as 180 mV. By measuring the reduction signals of a mixed sample with linear sweep vohammetry, and improving the resolution by taking semi-derivatives, dinitrophenol isomers were determined simultaneously and quantitatively. The linear calibration ranges were 1.0 × 10^-6 ～ 5.0×10^-4 moL/L for both 2,4- and 2,5-dinitrophenol, with detection limits of 2. 1× 10^-7 moL/L for 2,4- and 1.1 × 10^-7 moL/L for 2,5-dinitrophenol, respectively. This method was applied to the detection of dinitrophenols in artificial wastewater, and the recovery was from 97.6% to 103.3%.

关 键 词：碳纳米管 修饰电极 微分伏安 二硝基苯酚 测定 

分 类 号：O657.1[理学—分析化学]