Electrochemical deposition of Graphene Oxide- metal nano-composite on Pencil-Graphite Electrode for the high sensitivity detection of Bisphenol A by Adsorptive Stripping Differential Pulse Voltammetry

Abstract

Electrochemical platforms were developed based on pencil graphite electrodes (PGEs) modified electrochemically with reduced graphene oxide metal nanoparticles (ERGO–metalNPs) composite and used for the high-sensitivity determination of Bisphenol A (BPA) in water samples. Synergistic effects of both reduced Graphene Oxide sheets and metal nanoparticles on the performance of the pencil graphite electrode (PGE) were demonstrated in the oxidation of BPA by differential pulse voltammetry (DPV). A solution of graphene oxide (GO) 1 mg mL-1 and 15 ppm of metal stock solutions (1,000 mg L-1, atomic absorption standard solution) (Antimony or Gold) was prepared and after sonication deposited onto pencil graphite electrodes by cyclic voltammetry reduction. Different characterization techniques such as FT-IR, HR-SEM, XRD and Raman spectroscopy were used to characterize the GO and ERGO–metalNPs. Parameters that influence the electroanalytical response of the ERGO–SbNPs and ERGO–AuNPs such as, pH, deposition time, deposition potential, purging time were investigated and optimized. Well-defined, reproducible peaks with detection limits of 0.0125 μM and 0.062 μM were obtained for BPA using ERGO–SbNPs and ERGO–AuNPs respectively. The rGO-metalNPs–PGE was used for the quantification of BPA in tap water sample and proved to be suitable for the detection of BPA below USEPA prescribed drinking water standards of 0.087 μM.