铕离子掺杂类普鲁士蓝复合汞膜电极的制备及溶出分析特性

Preparation and Anodic Stripping Performance of Composite Mercury Film Electrode Modified with Europium-doped Prussian Blue Analogue

在铕离子掺杂类普鲁士蓝(Eu-PB)修饰的玻碳电极表面电沉积汞膜,制备了一种新型化学修饰复合汞膜电极GC/Eu-PB/MFE。研究了修饰层厚度、镀汞方式和汞膜成长过程对复合汞膜形成的影响。以Pb2+和Zn2+为探针离子,对复合汞膜电极和常规玻碳汞膜电极的氢过电位值、表面活性物质的影响、汞膜稳定性和金属离子的溶出伏安行为等进行了对比研究。同时,应用该电极结合示差脉冲阳极溶出伏安法对环境水样中的痕量Pb2+进行了测定。结果表明,Pb2+在该复合汞膜电极上的阳极溶出峰电流与其质量浓度在0.8～250μg/L范围有良好的线性关系(r=0.9995,n=12),检出限为0.2μg/L,加标回收率为98%～102%。用该法对国家铅标准物质溶液对比测定,数据的重复性和准确性均令人满意。

A novel composite mercury film electrode（ GC/Eu -PB/MFE） was prepared by electrode- positing mercury film on glassy carbon electrode modified with europium-doped prussian blue analogue （Eu - PB）. The effect of Eu - PB film thickness, mercury electrodepositing mode and mercury film growing procedure for building composite mercury film electrode were discussed. Hydrogen overvohage value of GC/Eu - PB/MFE and GC/MFE, the effect of surfactant and mercury film＇s stability and voltammetric behavior were contrastively studied using Pb2＋ and Zn2＋ as probe ions. The electrode was applied in the determination of lead in real water samples by differential pulse anodic stripping voltammetry. A good linearity between peak current and lead （ Ⅱ ） concentration was obtained in range of 0. 8 -250 μg/L（r = 0. 999 5, n = 12）, with detection limit of 0. 2 μg/L（S/N=3） and recoveries of 98% - 102%. In addition, the composite mercury film was also applied to the determi- nation of lead （ Ⅱ ） content of national standard matter solution as validity analysis, and the accuracy and precision were satisfactory.