A Novel Nonenzymatic Hydrogen Peroxide Sensor Based on a Polypyrrole Nanowire-Copper Nanocomposite Modified Gold Electrode

Abstract: A novel nonenzymatic hydrogen peroxide (H2O2) sensor has been fabricated by dispersing copper nanoparticles onto polypyrrole (PPy) nanowires by cyclic voltammetry (CV) to form PPy-copper nanocomposites on gold electrodes. Scanning electron microscopy (SEM) was used to characterize the morphologies of the PPy nanowires and the PPy-copper nanocomposite. The reactivity of the PPy-copper nanocomposite towards H2O2 was characterized by cyclic voltammetry and chronoamperometry. Effects of applied potential, the concentrations of detection solution upon the response currents of the sensor were investigated for an optimum analytical performance. It was proved that the PPy-copper nanocomposite showed excellent catalytic activity for the reduction of hydrogen peroxide (H2O2). The sensor showed a linear response to hydrogen peroxide in the concentration range between 7.0×10^-6 and 4.3×10^-3 mol L^-1 with a high sensitivity, and a detection limit of 2.3×10^-6 mol L^-1. Experiment results also showed that the sensor had good stability.