Green Synthesis of Reduced Graphene Oxide Decorated with Silver Nanoparticles Using Onosma bracteosa Leaf Extract for Efficient Electrochemical Detection of Hydrogen Peroxide

In this study, a simple, cost-effective and eco-friendly method was performed for the production of silver nanoparticle decorated reduced graphene oxide (rGO-Ag) nanocomposite using Onosma bracteosa leaf extract as reducing and stabilizing agent. The structure of the synthesized rGO-Ag nanocomposite was characterized by UV–Vis, XRD, SEM, TEM, EDX, and XPS. The synthesized rGO-Ag nanocomposite was used to fabricate an electrochemical sensor (rGO-Ag@GCE) for the determination of hydrogen peroxide. Electrochemical reduction of hydrogen peroxide was performed using DPV on rGO-Ag@GCE in 0.1 M PBS. The rGO-Ag@GCE exhibited good response in the linear concentration range of 25 µM to 800 µM, with a LOD of 0.11 µM. Amperometric measurements showed that the prepared sensor did not have a significant response to interfering species. Moreover, analysis of real samples demonstrated the potential of rGO-Ag@GCE as an electrochemical sensor for detecting hydrogen peroxide in commercial milk samples.