Sensitive electrochemical determination of copper (II) based on a glassy carbon electrode modified with ZnO/NiO/montmorillonite

Surface modification by nickel oxide and zinc oxide nanostructures and montmorillonite (MMT) on a glassy carbon electrode (ZnO/NiO/MMT-GCE) was employed in the present study as a novel electrode for sensitive determination of trace concentrations of Cu (II). Electrodeposition method has been selected in this study due to many advantages in comparison to other deposition techniques [1-3]. The morphology and properties of electrode surface were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. Electrochemical determination of Cu 2+ ions was performed by differential pulse voltammetry. The responses of modified electrode for Cu2+ was found to be improved significantly in comparison to those obtained using a conventional glassy carbon electrode. Under the optimized conditions the electrode exhibits a linear response to Cu (II) over a wide concentration range (5× 10-7 to 1.0 × 10-4 M) with the detection limit of 1.07×10-9 M.