Pt-nanoparticle incorporated carbon paste electrode for the determination of Cu(II) ion by anodic stripping voltammetry

Pt-nanoparticles were synthesized and introduced into a carbon paste electrode (CPE), and the resulting modified electrode was applied to the anodic stripping voltammetry of copper(II) ions. The synthesized Pt-nanoparticles were characterized by cyclic voltammetry, scanning electron microscopy and X-ray photoelectron spectroscopy techniques to confirm the purity and the size of the prepared Pt-nanoparticles (ca. 20 nm). This incorporated material seems to act as catalysts with preconcentration sites for copper(II) species that enhances the sensitivity of Cu(II) ions to Cu(I) species at a deposition potential of - 0.6 V in an aqueous solution. The experimental conditions, such as, the electrode composition, pH of the solution, pre-concentration time, were optimized for the determination of Cu(II) ion using as-prepared electrode. The sensitivity changes on the different binder materials and the presence of surfactants in the test solution. The interference effect of the coexisted metals were also investigated. In the presence of surfactants, especially TritonX-100, the Cu(II) detection limit was lowered to 3.9 x 10(-9) M. However, the Pt-nanoparticle modified CPE begins to degrade when the period of deposition exceeds to 10 min. Linear response for copper(II) was found in the concentration range between 3.9 x 10(-8) M and 1.6 x 10(-6) M, with an estimated detection limit of 1.6 x 10(-8) M (1.0 ppb) and relative standard deviation was 4.2% (n = 5).