还原氧化石墨烯-多壁碳纳米管复合膜负载金纳米粒子修饰玻碳电极检测双酚A

以水合肼为还原剂,采用均相还原法制备还原氧化石墨烯-多壁碳纳米管复合材料(rGO-MWCNTs),通过滴涂法将其修饰到玻碳电极(GCE)表面.以此复合材料为载体,采用电化学方法制备了金纳米粒子-还原氧化石墨烯-多壁碳纳米管复合膜修饰电极(AuNPs-rGO-MWCNTs/GCE).通过扫描电镜(SEM)、EDS能谱技术和电化学方法对此电极进行了表征.研究了双酚A在修饰电极上的电化学行为.结果表明,此电极对双酚A的电极过程具有良好的电化学活性,在0.10 mol/L PBS溶液(pH 7.0)中,微分脉冲伏安法测定双酚A的线性范围为5.0 × 10-9~1.0 × 10-7 mol/L和1.0 × 10-7~2.0 × 10-5 mol/L,检出限为1.0 ×10-9 mol/L(S/N=3). 将此电极用于模拟水样和超市购物小票样品中双酚A含量的测定,加标回收率分别为97%~110%和98%~104%.

Electrochemical Determination of Bisphenol A on a Glassy Carbon Electrode Modified with Gold Nanoparticles Loaded on ReducedGraphene Oxide-Multi-Walled Carbon Nanotubes Composite

A glassy carbon electrode (GCE) modified with gold nanoparticles loading on the reduced graphene oxide (rGO)-multi-walled carbon nanotubes (MWCNTs) composite film was fabricated by a two-step procedure.Firstly, rGO-MWCNTs composite were prepared by in-situ chemical reduction method with hydrazine as a reducing agent.Then, AuNPs were deposited on the surface of rGO-MWCNTs using simple cyclic voltammetry.This modified electrode was characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and electrochemical methods.Furthermore, the electrochemical behavior of bisphenol A (BPA) was also investigated using this modified electrode.The results showed that the modified electrode had high electrochemical activity for the oxidation of BPA.In 0.10 mol/L phosphate buffer solution (PBS, pH 7.0), the linear range for the determination of BPA with differential pulse voltammetry (DPV) was in the range of 5.0 × 10-9 -1.0 × 10-7 mol/L and 1.0 × 10-7-2.0 × 10-5 mol/L.The detection limit was 1.0 × 10-9 mol/L (S/N=3).The as-prepared modified electrode was successfully used to determine BPA in river water and the shopping receipt samples with recovery ranges of 97%-110% and 98%-104%, respectively.