Amperometric hydrogen peroxide sensor using a glassy carbon electrode modified with a nanocomposite prepared from...

A high-performance electrochemical H₂O₂ sensor was prepared by constructing multiple interfaces using platinum nanoparticles (Pt NPs), ferumoxytol (Fer) and reduced graphene oxide (rGO) on a glassy carbon electrode (GCE). The morphology of Fer/rGO and Fer/rGO-Pt was characterized by field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy. Cyclic voltammetry and chronoamperometry were adopted to characterize the electrochemical properties of the sensor. Because of the synergistic catalytic effect of the compositions (rGO, Fer and Pt NPs) on the multiple interfaces, the sensor exhibits particularly high electrocatalytic activity toward the reduction of H₂O₂ with a low detection limit (~0.38 μM), a linear range (0.0004-0.01, 0.0075-4.3 and 4.9-10.8 mM), and a high sensitivity (340 μA mM^-1 cm^-2, n = 4) operated at a typical working voltage of +0.1 V (vs. Ag/AgCl). The electrode is selective and long-term stable. It was successfully applied to the determination of H₂O₂ in (spiked) milk samples. Graphical abstract Schematic presentation of an electrochemical H₂O₂ sensor using platinum nanoparticles (Pt NPs), ferumoxytol (Fer) and reduced graphene oxide (rGO) nanocomposites modified glassy carbon electrode (GCE). The sensor was applied to the determination of H₂O₂ in (spiked) milk samples.