羧化碳纳米管修饰电极同时测定邻、对苯二酚

Simultaneous Detection of Catechol and Hydroquinone by Carboxylated Carbon Nanotubes Modified Electrode

采用滴涂法将羧化多壁碳纳米管(c-MWCNT)修饰于玻碳电极表面,以此修饰电极采用循环伏安法对邻苯二酚和对苯二酚进行测定,二者的氧化峰和还原峰峰电位差均超过100 m V,可实现对邻、对苯二酚的同时测定。对测定条件,包括底液p H、c-MWCNT修饰量进行了优化,研究了峰电流与扫描速度的关系。在优化的实验条件下,氧化峰电流与邻苯二酚和对苯二酚浓度在5. 00×10^(-5)～5. 00×10^(-3)mol/L范围内呈现良好的线性关系,检出限(S/N=3)分别为4. 30×10^(-6)mol/L和3. 80×10^(-6)mol/L,检测了加标自来水样和湖水样的回收率,获得了良好的结果。

Carboxylated multi-walled carbon nanotubes were modified onto glass carbon electrode by cast-coating method.With the as-prepared electrode,the electrochemical behavior and detection conditions of catechol and hydroquinone were explored by cyclic voltammetry.The results showed that both of the oxidation and reduction peak potential differences between catechol and hydroquinone exceeded 100 m V,which was sufficient to distinguish the two isomers.And the cathodic and anodic peak currents were proportional to the square root of scan rates,indicating that the electrochemical processes were diffusion controlled.In the phosphate buffer solution( p H 7. 38),the peak currents showed good linear relationships with concentrations of catechol and hydroquinone in the range of 5. 00×10^-5~ 5. 00×10^-3 mol/L with detection limits of 4. 30×10^-6 mol/L and 3. 80×10^-6 mol/L( S/N = 3),respectively.And the recovery rates of the spiked tap water and lake water were also in satisfied range.The method was facile,easy-operated and low-cost,and may be applied to detect catechol and hydroquinone in the polluted water.