pMB/MWNTs/GC电极对水体中苯二酚异构体的同时测定  

Simultaneous Voltammetric Determination of Dihydroxybenzene Isomers Using pMB/MWNTs/GC Electrode

作　　者：杨平华[1] 陈小艳[1] 万谦[1] 

机构地区：[1]九江学院化学化工学院,江西九江332005

出　　处：《分析测试学报》2010年第3期237-241,共5页Journal of Instrumental Analysis

基　　金：江西省教育厅科技资助项目(GJJ09352)

摘　　要：通过在多壁碳纳米管修饰玻碳电极上电聚合亚甲基蓝，制备了聚亚甲基蓝／碳纳米管／玻碳电极（pMB／MWNTs／GC）。用循环伏安法研究了3种苯二酚异构体在该电极上的电化学行为，结果表明，在pH7．0的磷酸盐缓冲溶液中，该修饰电极对苯二酚异构体的氧化表现出优异的电催化性能和选择性，对苯二酚、邻苯二酚和间苯二酚的氧化峰分别为0．104、0．203、0．609V（vs．SCE），峰电位差值分别为99、406mV。基于苯二酚异构体在pMB／MWNTs／GC修饰电极上的伏安行为，建立了苯二酚3种异构体同时分析的新方法。考察了各影响因素对测定的影响，最优实验条件下，在5．0×10^-6-1．5×10^-4mol·L^-1范围内，3种苯二酚异构体的阳极峰电流与其浓度存在线性关系，检出限均为1．0×10^-6mol·L^-1。将该法用于水体及冲洗废液中苯二酚异构体含量的测定，结果满意。A poly-methylene blue/multi-walled carbon nanotubes/glassy carbon（pMB/MWNTs/GC） electrode was fabricated by electropolymerization of methylene blue at a multi-walled carbon nanotubes modified glassy carbon electrode. The electrochemical performance of three dihydroxybenzenes, e.g. hydroquinone, catechol and resorcinol at the pMB/MWNTs/GC electrode was investigated by cyclic vohammetry. In pH 7.0 phosphate buffer solution （PBS）, hydroquinone, catechol and resorcinol yielded the oxidation peak at 0. 104 V, 0. 203 V and 0. 609 V （vs. SCE）, respectively. The differences of the oxidation peaks（△E） were 99 mV and 406 mV, respectively. The pMB/MWNTs/GC electrode showed excellent electrocatalytic activity and selectivity for dihydroxybenzenes. Based on their vohammetric behavior, a linear sweep voltammetry （LSV） was proposed for the simultaneous de- termination of three dihydroxybenzenes at the pMB/MWNTs/GC electrode. The experimental conditions, such as the acidity, supporting electrolyte and the interference on the determination of di- hydroxybenzenes have been studied. Under the optimal conditions, the calibration curves showed good linear relationship for three dihydroxybenzenes in the range of 5. 0 ×10^-6 - 1.5 ×10^-4 mol· L^-1 , and their detection limits were 1.0 ×10^-6 mol · L^-1. The proposed method had good repeatability and sensitivity, and was successfully applied in the determination of dihydroxybenzenes in real water samples.

关 键 词：聚亚甲基蓝/多壁碳纳米管/玻碳电极(pMB/MWNTs/GC) 苯二酚异构体 同时测定 水体 

分 类 号：O657.1[理学—分析化学] O625.31[理学—化学]