Silver nanoparticles prepared in presence of ascorbic acid and gelatin, and their electrocatalytic application

In this paper, we reported a simple and low-cost procedure to synthesize silver nanoparticles (AgNPs) by using ascorbic acid as reducing agent and gelatin as stabilizer. The synthesized AgNPs were characterized by various means such as transmission electron microscope (TEM), powder X-ray diffraction (XRD) and energy-dispersive X-ray (EDX). TEM observations and XRD analysis demonstrated that the size of AgNPs is about 20 nm. Silver nanoparticles modified with carbon-paste electrode (AgNPs-CPE) displayed excellent electrochemical catalytic activities towards hydrogen peroxide (H2O2). The reduction overpotential of H2O2 was decreased significantly compared with those obtained at the bare CPE. The sensor responded linearly to hydrogen peroxide (H2O2) in the concentration of 10-350 mu M, with detection limit of 5.6 mu M at 3 sigma using amperometry. The studied sensor exhibited good reproducibility and long-term stability.