▎ 摘　　要

Fully electrochemical methodology was used to prepare a new nanocomposite on a glassy carbon electrode. Graphene oxide was electrochemically reduced and deposited on the electrode surface. Poly-melamine was then formed by cyclic voltammetry on the prepared film. Finally, metallic copper nanoparticles were deposited on the resulting film by using cyclic voltammetry. Scanning electron microscopy and energy dispersive X-ray spectrometry were used for the characterization of the prepared film. The proposed electrode showed catalytic properties toward hydroquinone (HQ) and catechol (CC), as model analytes. The separation between oxidation peaks of HQ and CC was 105 mV in phosphate buffer (0.1 M, pH 7). Simultaneous determination of HQ and CC was performed by differential pulse voltammetry. The catalytic peak currents were linearly dependent on the concentrations of HQ and CC in the range of 2.0-566 and 2.0-181 mu M, with detection limits of 0.21 and 0.15 mu M, respectively. The sensitivity, stability and reproducibility of the sensor were studied. It was successfully applied to the analysis of HQ and CC in tap, lake and synthetic waste water samples. (C) 2015 The Electrochemical Society. All rights reserved.