GS-Nafion-Au Nanocomposite Film Modified SPCEs for Simultaneous Determination of Trace Pb2+ and Cd2+ by DPSV

摘要

An electrochemical sensor based on graphene sheets(GS)-Nafion-gold nanoparticles(Au)nanocomposite film modified screen-printed carbon electrodes(SPCEs) was fabricated(SPCEsS- 2+ 2+ Nafion/Au) for simultaneous determination of trace lead ions(Pb ) and cadmium ions(Cd ) in waterby differential pulse stripping voltammetry(DPSV). Scanning electron micrography(SEM) and X-raydiffraction(XRD) were employed to characterize the GS, Au preparation and the constructionprocesses of SPCEsS-Nafion/Au electrode. DPSV was used to study the electrochemical properties2+ 2+ of Pb and Cd . Under optimum experimental conditions, the stripping peak current showed good2+ 2+ -10 -8 -10 -8 linear relationship with Pb and Cd in the range of 5.010 .010 and 8.010 .010-10 2+ g/mL, respectively. The detection limit(3) were estimated to be around 2.310 g/mL for Pb and-10 2+ 3.510 g/mL for Cd . The recovery was 94%~106% in real water samples. The analytical resultswere compaprable with graphite furnace atomic absorption spectrometry(GFAAS) method. Theproposed SPCEsS-Nafion/Au electrode has high response current and enrichment ability due tomodified with composite nano-particles. It also showed the merits of disposable design, fewer samplevolume, portablity compared with other heavy metal ions electrochemical sensors. The convenient, fast2+ 2+ and sensitive voltammetric test method is suitable for analysis of Pb and Cd in water.