One-pot solvothermal synthesis of a Cu2O/Graphene nanocomposite and its application in an electrochemical sensor for dopamine

Nanocomposites composed of cuprous oxide (Cu2O) and graphene were synthesized via reduction of copper(II) in ethylene glycol. This material possesses the specific features of both Cu2O and graphene. Its morphology was characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and Xray photoelectron spectroscopy. Cyclic voltammetry was used to evaluate the electrochemical response of a glass carbon electrode (GCE) modified with the nanocomposite towards dopamine (DA). Compared to the bare GCE, the Cu2O nanoparticles modified electrode and the graphene modified electrode, the nanocomposites modified electrode displays high electrocatalytic activity in giving an oxidation peak current that is proportional to the concentration of DA in the range from 0.1 to 10 mu M, with a detection limit of 10 nM (S/N = 3). The modified electrode shows excellent selectivity and sensitivity even in the presence of high concentration of uric acid and can be applied to determine DA in real samples with satisfactory results.