A Novel H2O2 Amperometric Sensor based on Prussian Blue/Palladium Nanoparticles/Graphene Oxide Nanocomposite Modified Electrode

A novel nanocomposite consisting of graphene oxide (GO), palladium nanoparticles (PdNPs) and Prussian blue (PB) was used to fabricate a non-enzymatic hydrogen peroxide (H2O2) sensor. A pencil graphite electrode (PGE) was modified with the mentioned nanocomposite (PB/Pd/GO-PGE) and characterized by several techniques including scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The sensor showed a significant better electrocatalytic activity for the reduction of hydrogen peroxide in comparison with the single GO-PGE, PB/GO-PGE and Pd/GO-PGE. This was attributed to the synergistic effect of PB, Pd, and GO nanoparticles. The values of diffusion coefficient, D, and electroreduction kinetics parameters including electron transfer coefficient, , and catalytic rate constant, k, were 9.61×10-6 cm2 s-1,0.5 and 7.02×105 cm3 mol-1 s-1 respectively. Furthermore, the proposed sensor demonstrated a high level of the overall performance for the analysis of H2O2 using hydrodynamic amperometry in the concentration range from 0.2×10-6 to 0.5×10-3 mol L-1 and detection limit of 0.078×10-6 mol L-1 with good stability, repeatability, and selectivity. This modified electrode was also used successfully for the determination of H2O2 in real samples such as, mother’s milk, and rain water.