Electrocatalytic Reduction of Hydrogen Peroxide and Its Non-Enzymatic Electrochemical Detection Using Silver Nanoparticles Anchored on Reduced Graphene Oxide

Abstract

Silver-reduced graphene oxide (Ag-rGO) nanohybrid was synthesized by applying a slight modification to the Turkevich method using trisodium citrate as a reducing and stabilizing agent to catalyze the non-enzymatic electrochemical detection of hydrogen peroxide (H2O2). Spherical silver nanoparticles (AgNPs) with an average particle size of 2.2 nm surfaced on reduced graphene oxide (rGO) sheets. Cyclic voltammograms (CV) obtained from glassy carbon (GC) electrode coated with Ag-rGO nanohybrid (4 mM) exhibited a peak at an overpotential of -0.52 V, with a larger faradaic current for the reduction of H2O2. Using the modified electrode for the linear sweep voltammetry (LSV) detection of H2O2, the detection limit and sensitivity were determined to be 4.8 μM (S/N ═ 3) and 0.0262 μA μM−1, respectively. The sensor appeared selective and stable towards H2O2 in the presence of possible interference, and it also demonstrated good recoveries of H2O2 concentration in real water samples.