用聚苏木精/TiO_2-石墨烯复合膜修饰玻碳电极差分脉冲伏安法测定水样中对苯二酚

Determination of hydroquinone in water by differential pulse voltammetry with polyhematoxylin/TiO2-graphene composite film modified glassy carbon electrode

采用滴涂法和电聚合法制备了聚苏木精/TiO2-石墨烯复合膜修饰玻碳电极,用循环伏安法研究了对苯二酚(HQ)在修饰电极上的电化学行为。实验结果表明,该修饰电极对于HQ的氧化还原具有良好的电催化性能。相对于裸电极和TiO2-石墨烯修饰电极,HQ在聚苏木精/TiO2-石墨烯修饰玻碳电极上的氧化峰电流显著提高。利用差分脉冲伏安法测定,HQ在3.0×10-6～1.0×10-3 mol/L浓度范围内与氧化峰电流呈良好的线性关系,相关系数为0.993。信噪比为3时,HQ检出限为1.0×10-7 mol/L。将该方法用于环境水样分析,HQ的回收率为96.2%～105.6%。

TiO2-graphene（TiO2-Gr） was coated on glassy carbon electrode（GCE） and hematoxylin was then electropolymerized on the modified electrode to fabricate an electrochemical sensor（polyhematoxylin/TiO2-graphene composite film modified glassy carbon electrode）.The electrochemical behaviors of hydroquinone（HQ） on the modified electrode were investigated by cyclic voltammetry.The experimental results showed that the modified electrode had good electrocatalysis performance toward the redox of HQ.The oxidation peak current obviously improved compared to that on the bare GCE and TiO2-Gr/GCE.Differential pulse voltammetry was used for the determination of HQ.The concentration of HQ in the range of 3.0×10^-6-1.0×10^-3 mol/L showed good linear relationships with the oxidation peak current,with correlation coefficient（R） of 0.993.The detection limit was 1.0×10^-7 mol/L（S/N=3）.The developed method was used to determination of enviromental water samples with recoveries of 96.2%-105.6%.