聚对氨基苯磺酸/石墨烯修饰玻碳电极伏安法测定痕量汞

制备了对氨基苯磺酸/石墨烯复合膜修饰电极，研究了汞在修饰电极上的电化学行为。 在0.1 mol/L、pH=4.0的磷酸盐缓冲液中，以此修饰电极为工作电极，在-1.2 V搅拌富集5 min，用差分脉冲伏安法测定0.31 V处的溶出峰电流。 结果表明，该电极显著提高了汞离子的电化学响应信号。 在优化条件下，峰电流与Hg2+的浓度在1.0×10-6~5.0×10-4 mol/L范围内呈良好的线性关系，相关系数为0.995。 方法的检出限为5.0×10-7 mol/L。 将该法用于水样中痕量汞的测定，回收率为92.2%~105.2%。

Determination of Trace Amount of Mercury Using Poly(p-Aminobenzene Sulfonic Acid)/Graphene Modified Glassy Carbon Electrode

A poly(p-aminobenzene sulfonic acid)/graphene composite modified glassy carbon electrode(GCE) was fabricated and the electrochemical behaviors of mercury on the modified electrode were investigated. The results show that the electrochemical response of Hg2+ at the modified electrode is significantly improved compared with the bare GCE. After 5 min accumulation at -1.2 V in a 0.1 mol/L pH=4.0 PBS, the peak currents vary linearly with the concentration of Hg2+ over the range from 1.0×10-6 to 5.0×10-4 mol/L with the detection limit of 5.0×10-7 mol/L. The correlation coefficiency is 0.995. Using this modified electrode, trace amounts of Hg2+ in water samples are determined with recoveries of 92.2%~105.2%.