Petal-like CuO nanostructures prepared by a simple wet chemical method, and their application to non-enzymatic amperometric determination of hydrogen peroxide

Uniform and petal-like CuO nanostructures have been deposited on a copper foil substrate by a simple wet chemical method at room temperature through oxidation of elemental copper in strongly alkaline solution. The concentration of NaOH in the precursor solution is critical for the product morphology. The morphology of the CuO nanostructures was characterized by scanning electron microscopy and their crystal structure was studied by X-ray diffraction. Their electrochemical performance was evaluated by cyclic voltammetry, amperometry, and electrochemical impedance spectroscopy. The CuO films are shown to represent active electrode materials for non-enzymatic amperometric determination of H2O2. Response to H2O2 in solutions of pH 7.4 at a working potential of -200 mV (vs. Ag/AgCl) is linear in the 10 to 960 mu M concentration range, with the detection limit 2.1 mu M and the sensitivity 5030 mu Aa (TM) mM(-1). Its excellent electrocatalytic activity, large specific surface area, efficient mass transport and electron transfer properties make this electrode a highly sensitive and reliable tool for electrochemical determination of H2O2.