Synthesis of dendritic silver nanostructures and their application in hydrogen peroxide electroreduction

Well-defined silver (Ag) dendritic nanostructures were successfully synthesized by electrodeposition without the use of any template or surfactant. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to investigate the as-prepared Ag nanomaterials. These dendrites are aggregates of Ag nanoparticles, which are highly crystalline in nature. The concentration of AgNO3 affects the shape of the nanoparticles. In addition, the electrochemical properties of the Ag dendrite-modified glassy carbon electrode (Ag/GC) were characterized by cyclic voltammetry and chronoamperometry. Results indicated that the as-obtained Ag dendrites exhibited favorable electroreduction activity towards oxygen (O-2) and hydrogen peroxide (H2O2). When used as a sensor. the Ag/GC electrode exhibited a wide linear range of 0.005-12 mM H2O2, with a remarkable sensitivity of 7.39 mu A/mM, a detection limit of 0.5 mu M, estimated at a signal-to-noise ratio of 3, and a rapid response time (within 5s). Moreover, the electrode showed good reproducibility, anti-interferant ability and long-term stability. (C) 2011 Elsevier Ltd. All rights reserved.