Synthesis of core/satellite donut-shaped ZnO-Au nanoparticles incorporated with reduced graphene oxide for electrochemical sensing of rutin

Novel core/satellite donut-shaped ZnO-Au nanoparticles (ZnO-Au NPs) were successfully prepared by direct growth of Au nanoparticles on the surface of donut-shaped ZnO. Furthermore, graphene was effectively introduced using the hydrothermal method to construct core/satellite donut-shaped ZnO-Au nanoparticles/reduced graphene oxide composites (ZnO-Au NPs/rGO). The composites were characterized by using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray spectroscopy (EDS), X-ray powder diffraction (XRD) and electrochemical methods. The possible formation mechanism was preliminary proposed. The prepared composites were used to construct an electrochemical sensor, and achieved sensitive electrochemical determination of rutin. The electrochemical behavior of rutin at the ZnO-Au NPs/rGO sensor was investigated. Under the optimal conditions, rutin had a significantly increased electrochemical response with a wide detection range of 0.06-6.0 mu mol L-1 and low detection limit of 1.0 nmol L-1 (S/N = 3).