Electrodeposition of zinc hydroxide on carbon graphite electrode for electrochemical determination of trace copper in water samples using square wave anodic stripping voltammetry

Abstract

A novel inexpensive and easy electrochemical sensor based on carbon graphite electrode (Gr) modified with zinc hydroxide has been developed for the determination of trace levels of copper using square wave anodic stripping voltammetry (SWASV). The influences of experimental SWASV parameters on the sensitivity of the proposed method, such as the effects of deposition potential, accumulation time and frequency were investigated. Under optimal conditions, the proposed method showed linear relationship between the currents and the concentrations of Cu(II) in the range between 1.00 × 10−8 mol L−1 and 6.00 × 10−7 mol L−1 and a low detection limit of 9.03 × 10−10 mol L−1. In addition, the developed electrode displayed a good repeatability with relative standard deviations of 0.85% after seven determinations, the interference experiments show that ten ionic species had little influence on the SWASV signals of Cu(II). The method was validated using two different brands of local source water and the results was very satisfactory by showing a recovery values between 103.7 and 108.4%.