Facile synthesis of three-dimensional porous Au@Pt core-shell nanoflowers supported on graphene oxide for highly sensitive and selective detection of hydrazine

A novel strategy is developed to synthesize three-dimensional porous Au@Pt core-shell nanoflowers supported on GO (Au@Pt-nFs/GO) for enhanced electrochemical sensing of hydrazine (N 2 H 4 ). Au@Pt-nFs/GO nanocomposite was synthesized through a facile and green method, where ascorbic acid and chitosan were employed as the reductant and linking agent, respectively. The experiment results revealed that a large numbers of Au@Pt-nFs with Au cores and Pt dendritic shells were distributed on the surface of GO sheets. Meanwhile, Au@Pt-nFs/GO with large surface area, abundant active sites and open structure reduced the overpotential and accelerated kinetics of N 2 H 4 oxidation, therefore making the sensor based on Au@Pt-nFs/GO exhibit an excellent performance for N 2 H 4 analysis with a wide linear range of 0.8   μM–0.429   mM, a high sensitivity of 1695.3   μA   mM −1   cm −2 and a low detection limit of 0.43   μM (S/N   =   3). Moreover, the sensor also exhibited good selectivity, repeatability and stability. Application of the sensor for the detection of N 2 H 4 in tap water samples was demonstrated.